Philip Bucksbaum
Marguerite Blake Wilbur Professor of Natural Science and Professor of Photon Science, of Applied Physics and of Physics
Photon Science Directorate
Bio
Phil Bucksbaum holds the Marguerite Blake Wilbur Chair in Natural Science at Stanford University, with appointments in Physics, Applied Physics, and in Photon Science at SLAC. He conducts his research in the Stanford PULSE Institute (https://web.stanford.edu/~phbuck). He and his wife Roberta Morris live in Menlo Park, California. Their grown daughter lives in Toronto.
Bucksbaum was born and raised in Iowa, and graduated from Harvard in 1975. He attended U.C. Berkeley on a National Science Foundation Graduate Fellowship and received his Ph.D. in 1980 for atomic parity violation experiments under Professor Eugene Commins, with whom he also has co-authored a textbook, “Weak Interactions of Leptons and Quarks.” In 1981 he joined Bell Laboratories, where he pursued new applications of ultrafast coherent radiation from terahertz to vacuum ultraviolet, including time-resolved VUV ARPES, and strong-field laser-atom physics.
He joined the University of Michigan in 1990 and stayed for sixteen years, becoming Otto Laporte Collegiate Professor and then Peter Franken University Professor. He was founding Director of FOCUS, a National Science Foundation Physics Frontier Center, where he pioneered research using ultrafast lasers to control quantum systems. He also launched the first experiments in ultrafast x-ray science at the Advanced Photon Source at Argonne National Lab. In 2006 Bucksbaum moved to Stanford and SLAC, and organized the PULSE Institute to develop research utilizing the world’s first hard x-ray free-electron laser, LCLS. In addition to directing PULSE, he has previously served as Department Chair of Photon Science and Division Director for Chemical Science at SLAC. His current research is in laser interrogation of atoms and molecules to explore and image structure and dynamics on the femtosecond scale. He currently has more than 250 publications.
Bucksbaum is a Fellow of the APS and the Optical Society, and has been elected to the National Academy of Sciences and the American Academy of Arts and Sciences. He has held Guggenheim and Miller Fellowships, and received the Norman F. Ramsey Prize of the American Physical Society for his work in ultrafast and strong-field atomic and molecular physics. He served as the Optical Society President in 2014, and also served as the President of the American Physical Society in 2020. He has led or participated in many professional service activities, including NAS studies, national and international boards, initiatives, lectureships and editorships.
Academic Appointments
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Professor, Photon Science Directorate
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Professor, Physics
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Professor, Applied Physics
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Member, Bio-X
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Principal Investigator, Stanford PULSE Institute
Administrative Appointments
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Chair, Department of Photon Science, SLAC, Stanford University (2023 - 2026)
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President, American Physical Society (2020 - 2020)
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President, The Optical Society (2014 - 2014)
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Visiting Professor of Physics, Weizmann Institute of Science (2013 - 2013)
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Marguerite Blake Wilbur Professor in Natural Science, Stanford University (2009 - Present)
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Chair, Department of Photon Science, SLAC, Stanford University (2007 - 2010)
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Director of the Stanford PULSE Institute, Stanford University and SLAC (2006 - Present)
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Professor of Physics, Applied Physics, and the Stanford Synchrotron Radiation Laboratory, Stanford University (2006 - Present)
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Peter Frankin Distinguished University Professor, University of Michigan (2005 - 2006)
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Visiting Scholar, Department of Applied Physics and SSRL, Stanford University (2004 - 2005)
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Director of FOCUS, The Center for Frontier Optical Coherent Ultrafast Science (2001 - 2005)
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Otto Laporte Collegiate Professor, College of Literature, Science, and the Arts, University of Michigan (1998 - 2005)
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Visiting Research Investigator, Service des Photons, Atomes et Molecules, Centre d'Etudes de Saclay, Commissariat a l'Energie Atomique (1997 - 1997)
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Miller Visiting Professor of Physics and Electrical Engineering, University of California, Berkeley (1996 - 1996)
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Professor of Physics, University of Michigan (1990 - 1998)
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Adjunct Associate Professor of Applied Physics, Columbia University (1989 - 1990)
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Principal Investigator Member of Technical Staff, Physics Research Division, AT&T Bell Laboratories (1982 - 1990)
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Post-doctoral research, AT&T Bell Laboratories (1981 - 1982)
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Post-doctoral research, Lawrence Berkeley Laboratories (1980 - 1981)
Honors & Awards
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Norman F. Ramsey Prize, American Physical Society (2020)
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Member, National Academy of Sciences (2004)
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Fellow, American Academy of Arts and Sciences (2012)
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Fellow, American Physical Society (1990)
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Fellow, Optical Society (1995)
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Marguerite Blake Wilbur Professor in Natural Science, Stanford University (2009)
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Peter Franken University Professor, University of Michigan (2005)
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Otto Laporte Professor Collegiate of Physics, University of Michigan (1998)
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Distinguished Faculty Research Award, Univeristy of Michigan (1996)
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Extraordinary Contribution Award, AT&T Bell Laboratories (1987, 1988, 1989)
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Post-doctoral Fellowship, NATO (1981)
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Graduate Fellowship, NSF (1975 - 1978)
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Distinguished Traveling Lecturer, Division of Laser Science, American Physical Society (1996 - 1999)
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APS Centennial Speaker, APS (1998 - 1999)
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Centennial Speaker, American Physical Society (1998 - 1999)
Boards, Advisory Committees, Professional Organizations
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Vice President (2018); President-Elect (2019); President (2020); Past President (2021), American Physical Society (2018 - Present)
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Board Member, Vice-President (2012), President-Elect (2013), President (2014), Past President (2015), Optical Society (2012 - 2015)
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Chair, National Academy of Sciences Physics Section (2016 - 2019)
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Chair, Board on Physics and Astronomy of the National Research Council (2011 - 2013)
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Chair, AMO 2010, the National Academy of Sciences decadal study of AMO physics (2005 - 2006)
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Chair, "Reaching for the Brightest Light," National Academy consensus study on high intensity laser science and opportunities (2015 - 2017)
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Chair, NSF Committee of Visitors Subcommittee on AMO Physics and Quantum Information Science, for the Math and Physical Sciences Directorate (2011 - 2012)
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Chair, Science Advisory Subcommittee for the APS Upgrade in Ultrafast Science (2011 - 2012)
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Member, Weizmann Institute of Sciences International Board of Directors (2012 - Present)
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Member, Steering Committee, National Photonics Initiative (2013 - Present)
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Member, Math and Physical Sciences Advisory Committee for the National Science Foundation (2013 - 2019)
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Member, Committee of Visitors for NSF Physics Division, Mathematics and Physical Sciences Directorate (2019 - 2019)
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Member, Physical Review Letters Advisory Board (2012 - 2016)
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Member, Advanced Light Source Crosscut Review on AMO Physics (2013)
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Member, LBNL Molecular Foundry Science Advisory Committee (2012)
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Member, Max Planck Institute for Quantum Optics Science Advisory Committee (2012)
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Physics Class Representative, Class Membership Committee of the National Academy of Sciences (2012)
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Member, QANU International Evaluation Committee for Physics in The Netherlands (2011)
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Director, Division of Chemical Sciences, Photon Science Directorate, SLAC (2011 - 2011)
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Member, Science Advisory Committee for the Advanced Photon Source at Argonne (2010)
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Member, National Research Council Committee for Physics at NIST (2010 - 2012)
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Chair, Stanford University Applied Physics Graduate Admissions Committee (2010 - 2011)
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Chair, Stanford University Physics and Applied Physics Graduate Orientation and Open House Committees (2010 - 2011)
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Member, Stanford University Physics Graduate Curriculum Committee (2010 - 2011)
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Member, Stanford University Physics Graduate Admissions Committee (2010 - 2011)
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Member, Stanford University Physics AMO Search Committee (2010 - 2011)
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Member, Harvard Physics Visiting Committee (2009)
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Member, Stanford University Applied Physics Joint Appointments Committee (2008 - 2009)
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Member, Advisory Board of the Materials Research Laboratory, University of Illinois at Urbana-Champaign (2007 - 2010)
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Chair, 2007 Quantum Control Gordon Research Conference (2007)
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Member, UCSB iQCD External Review Committee (2007)
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Chair SLAC Faculty Task Force, Department of Photon Science, SLAC, Stanford University (2007 - 2010)
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Member, Stanford University Applied Physics Graduate Admissions Committee (2007 - 2010)
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Member, Stanford University Physics Graduate Admissions Committee (2007 - 2010)
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Member, Stanford University Physics AMO Search Committee (2007 - 2009)
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Strategic Planning Committee, SLAC Associate Laboratory Director for LCLS (2007 - 2008)
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Member, Stanford University Applied Physics Photonics Seminar Committee (2007 - 2007)
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Member, Board on Physics and Astronomy of the National Research Council (2006 - 2012)
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Member, Stanford University Materials Science/SSRL Faculty Search Committee (2006)
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Member, Advisory Board of the NSF ERC for Extreme Ultraviolet Science (2006 - 2012)
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Member, Board on Physics and Astronomy of the National Research Council (2006 - 2010)
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Member, Advisory Committee of Physics Today (2006 - 2009)
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Member, Science Advisory Committee for the Advanced Light Source at Berkeley (2006 - 2009)
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Member, Stanford University SSRL Condensed Matter Theory Search Committee (2006 - 2007)
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Member, Stanford University Physics AMO Search Committee (2006 - 2007)
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Member, Stanford University Applied Physics special faculty appointment committee (2006 - 2007)
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Space Working Group, SLAC (2006 - 2007)
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Member, BESAC (The Basic Energy Sciences Advisory Committee to the Office of Science, Department of Energy (2005)
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Member, University of Michigan faculty search committee (2005)
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Member, BESAC Grand Challenges Committee (2005 - 2007)
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Member, DOE-Basic Energy Sciences committee to review the 25-year plan for major facilities (2004)
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Members, University of Michigan (2005) Membership in the N (2004)
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Member, Harvard ITAMP External Advisory Board (2004 - 2007)
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Chair, American Physical Society nominating committee (2004 - 2004)
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Member, NAS Committee on AMO Science (CAMOS) (2003 - 2005)
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Editor, Virtual Journal of Ultrafast Science (2002 - 2012)
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Divisional Associate Editor, Physical Review Letters (2002 - 2009)
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Divisional Associate Editor, Physical Review Letters (2002 - 2008)
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Member, SAUUL advisory group (2002 - 2004)
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Member, University of Michigan AMO Faculty search committee (2002 - 2003)
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Member, BESAC (The Basic Energy Sciences Advisory Committee to the Office of Science, Department of Energy (2001 - 2005)
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Member, University of Michigan Departmental Internal Review Committee (2001 - 2005)
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Executive Board Member, American Physical Society (2001 - 2002)
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General Co-Chair, Quantum Electronics and Laser Science Meeting (1999)
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Member, Leone Panel, to review 4th generation synchrotron facilities (1999)
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Member, Science Advisory Committee for the SLAC Linac Coherent Light Source (LCLS) (1999 - 2009)
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Member, National Academy Committee to update the FAMOS report: Future of Atomic, Molecular, and Optical Science (1999 - 2001)
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Chairman, University of Michigan AMO Faculty search committee (1999 - 2000)
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Co-author, Science Case for X-ray Free Electron Lasers, commissioned by Basic Energy Sciences, Department of Energy (1999 - 2000)
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Member, Program Committees for the APS Annual Meeting Division of Atomic, Molecular and Optical Physics (1999 - 2000)
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Member, University of Michigan Graduate Concerns Committee (1999 - 2000)
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Member, University of Michigan Graduate Admissions Committee (1998 - 2005)
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General Coucilor at Large, American Physical Society (1998 - 2002)
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Member, University of Michigan Long Range Plan Committee (1998 - 2000)
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Member, University of Michigan faculty search committee for Physical Chemistry (1998 - 2000)
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Chairman, Rackham Divisional Board (1998 - 1999)
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Chairman, DoE-BES Report on Future Directions of High Field Interactions Atoms and Molecules with Photons (1997)
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Co-Chairman, US-Japan Seminar on Coherent Manipulation of Matter (1997)
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Program Co-Chairman, Quantum Electronics and Laser Spectroscopy Meeting (1997)
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Member, Program Committee for the International Conference on Multiphoton Processes, Garmisch-Partenkirchen, Germany (1996)
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Member, Special NSF Review Panel for Stanford/LIGO project (1996)
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Miller Visiting Professor of Physics and Electrical Engineering, University of California, Berkeley, CA 94720 (1996)
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Participant, National Research Council Workshop on Research and Education in Optical Science and Engineering, Irvine (1996)
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Session Organizer and Local Committee Member, APS Division of Atomic, Molecular, and Optical Physics (1996)
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Member, Technical Advisory Committee for the Laser Program, LLNL (1996 - 2000)
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Fellow, John Simon Guggenheim Memorial Foundation (1996 - 1997)
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Member, University of Michigan Awards and Prizes Committee (1996 - 1997)
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Chair, NSF Special Emphasis Panel on Manipulating Matter with Light, Cambridge, MA, (1995)
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Member, Fellowship Committee for the Laser Science Topical Group of the APS (1995)
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Member, University of Michigan Computing Committee (1995)
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Rosenberg Lecturer in Physics, Yale University (1995)
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Chair, University of Michigan Physics/Chemistry faculty appointment committee (1995 - 1996)
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Acting Director, University of Michigan Center for Ultrafast Optical Science (1994)
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Member, Program Committee for the International Conference on Atomic Physics (1994)
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Member, Program Committee for the OSA Topical Meeting on High Field Interactions and Short Wavelength Generation, St. Malo (1994)
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Member, Program Committee for the OSA Topical Meeting on Ultrafast Processes, California (1994)
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Participant, National Academy Panel on Future Free Electron Lasers, Washington (1994)
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Member, University of Michigan Physics Department Executive Committee (1994 - 1996)
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Member, Fellows Committee for the APS Topical Group on Precision Measurements (1993)
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Program Committee, Optical Society Topical Meeting on Short Wavelength Coherent Radiation: Generation and Applications; San Diego, CA (1993)
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Director, Fellows Program at the NSF Center for Ultrafast Optical Science (1993 - 2000)
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Member, faculty promotions and appointments committee of LS&A (1993 - 1996)
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Member, Program Committee for the Annual Meeting of the Optical Society (1993 - 1995)
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Member, Executive Committe of the Division of Atomic, Molecular, and Optical Physics of the APS (1993 - 1995)
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Member, selection committee for the APS Award for Outstanding Doctoral Thesis Research in AMO Physics (1993 - 1994)
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Member, National Research Council selection panel for NRC Postdoctoral Fellowships (1993 - 1994)
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Member, AIP expert panel on new publishing directions (1992)
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Member, selection committee for the Rackham Research Partnership Fellowship Awards (1992)
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Member, International Physics Advisory Panel, IUPAP (1992)
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Member, Program Committee for the International Laser Spectroscopy Conference (1992 - 1995)
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Chair, Optical Science Division (1992 - 1994)
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Member, Technical Executive Council of the Optical Society of America (1992 - 1994)
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Co-editor, University of Michigan Rich Memorial Symposium Proceedings (1992 - 1992)
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Member, University of Michigan Administrative Services Review Committee (1992 - 1992)
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Member, University of Michigan Building Committee (1992 - 1992)
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Member, University of Michigan Rich Memorial Symposium Organizing Committee (1992 - 1992)
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Program Chairman, Laser Spectroscopy Subcommittee, Conference on Quantum Electronics and Laser Spectroscopy (QELS'91), Baltimore, Maryland (1991)
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Associate Director for Science, University of Michigan Center for Ultrafast Optical Science (1991 - 2000)
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Chair, University of Michigan Target of Opportunity Committee (1991 - 1995)
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Chairman, University of Michigan Atomic, Molecular, and Optical Physics Recruitment and Advisory Committee (1991 - 1995)
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Member, Program Committee and Session Organizer of the APS annual meeting for AMO Physics (1991 - 1995)
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Member, Laser Spectroscopy Subcommittee, International Quantum Electronics Conference (IQEC'90), Los Angeles, CA (1990)
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Colloquium committee member, University of Michigan Atomic, Molecular, and Optical Physics Recruitment and Advisory Committee (1990 - 1991)
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Membership, Advisory Committee for Research at AT&T Bell Laboratories (1989 - 1990)
Professional Education
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Ph.D, University of California, Berkeley, Physics (1980)
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M.A., University of California, Berkeley, Physics (1978)
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A.B Magna cum Laude, Harvard University, Physics (1975)
2024-25 Courses
- Lasers, Lasers, Nothing but Lasers
PHYSICS 11N (Aut) - Ultrafast Quantum Physics
APPPHYS 283, PHOTON 283 (Win) -
Independent Studies (5)
- Curricular Practical Training
APPPHYS 291 (Aut, Win, Spr, Sum) - Directed Studies in Applied Physics
APPPHYS 290 (Aut, Win, Spr, Sum) - Independent Research and Study
PHYSICS 190 (Aut, Win, Spr, Sum) - Research
PHYSICS 490 (Aut, Win, Spr, Sum) - Senior Thesis Research
PHYSICS 205 (Aut, Win, Spr, Sum)
- Curricular Practical Training
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Prior Year Courses
2023-24 Courses
- Ultrafast Quantum Physics
APPPHYS 283, PHOTON 283 (Win)
2022-23 Courses
- Ultrafast Quantum Physics
APPPHYS 283, PHOTON 283 (Win)
2021-22 Courses
- Advanced Topics in AMO Physics
APPPHYS 384, PHOTON 384 (Win) - Light and Heat
PHYSICS 45 (Aut) - Ultrafast Quantum Physics
APPPHYS 283, PHOTON 283 (Spr)
- Ultrafast Quantum Physics
Stanford Advisees
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Doctoral Dissertation Reader (AC)
River Robles, Nan Wang -
Postdoctoral Faculty Sponsor
Chuan Cheng, Ishita Kemeny -
Doctoral Dissertation Advisor (AC)
Ian Gabalski, Andy Howard, Erik Isele, Emily Thierstein, Jun Wang, Eleanor Weckwerth -
Doctoral (Program)
Sara Irvine, Supavit Pokawanvit, Yueheng Shi, Josephine Yu, Janet Zhong
All Publications
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Exploring the ultrafast and isomer-dependent photodissociation of iodothiophenes via site-selective ionization.
Physical chemistry chemical physics : PCCP
2024
Abstract
C-I bond extension and fission following ultraviolet (UV, 262 nm) photoexcitation of 2- and 3-iodothiophene is studied using ultrafast time-resolved extreme ultraviolet (XUV) ionization in conjunction with velocity map ion imaging. The photoexcited molecules and eventual I atom products are probed by site-selective ionization at the I 4d edge using intense XUV pulses, which induce multiple charges initially localized to the iodine atom. At C-I separations below the critical distance for charge transfer (CT), charge can redistribute around the molecule leading to Coulomb explosion and charged fragments with high kinetic energy. At greater C-I separations, beyond the critical distance, CT is no longer possible and the measured kinetic energies of the charged iodine atoms report on the neutral dissociation process. The time and momentum resolved measurements allow determination of the timescales and the respective product momentum and kinetic energy distributions for both isomers, which are interpreted in terms of rival 'direct' and 'indirect' dissociation pathways. The measurements are compared with a classical over the barrier model, which reveals that the onset of the indirect dissociation process is delayed by ∼1 ps relative to the direct process. The kinetics of the two processes show no discernible difference between the two parent isomers, but the branching between the direct and indirect dissociation channels and the respective product momentum distributions show isomer dependencies. The greater relative yield of indirect dissociation products from 262 nm photolysis of 3-iodothiophene (cf. 2-iodothiophene) is attributed to the different partial cross-sections for (ring-centred) π∗ ← π and (C-I bond localized) σ∗ ← (n/π) excitation in the respective parent isomers.
View details for DOI 10.1039/d3cp06079a
View details for PubMedID 38616653
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Experimental demonstration of attosecond pump-probe spectroscopy with an X-ray free-electron laser
NATURE PHOTONICS
2024
View details for DOI 10.1038/s41566-024-01419-w
View details for Web of Science ID 001200371400001
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Multiparticle cumulant mapping for Coulomb explosion imaging: Calculations and algorithm
PHYSICAL REVIEW A
2024; 109 (4)
View details for DOI 10.1103/PhysRevA.109.042802
View details for Web of Science ID 001198598600015
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Applying Bayesian inference and deterministic anisotropy to retrieve the molecular structure ÷Ψ(<bold>R</bold>)÷<SUP>2</SUP> distribution from gas-phase diffraction experiments
COMMUNICATIONS PHYSICS
2023; 6 (1)
View details for DOI 10.1038/s42005-023-01420-9
View details for Web of Science ID 001123559000001
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X-ray induced Coulomb explosion imaging of transient excited-state structural rearrangements in CS<sub>2</sub>
COMMUNICATIONS PHYSICS
2023; 6 (1)
View details for DOI 10.1038/s42005-023-01414-7
View details for Web of Science ID 001095830300001
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Femtosecond Electronic and Hydrogen Structural Dynamics in Ammonia Imaged with Ultrafast Electron Diffraction.
Physical review letters
2023; 131 (14): 143001
Abstract
Directly imaging structural dynamics involving hydrogen atoms by ultrafast diffraction methods is complicated by their low scattering cross sections. Here we demonstrate that megaelectronvolt ultrafast electron diffraction is sufficiently sensitive to follow hydrogen dynamics in isolated molecules. In a study of the photodissociation of gas phase ammonia, we simultaneously observe signatures of the nuclear and corresponding electronic structure changes resulting from the dissociation dynamics in the time-dependent diffraction. Both assignments are confirmed by ab initio simulations of the photochemical dynamics and the resulting diffraction observable. While the temporal resolution of the experiment is insufficient to resolve the dissociation in time, our results represent an important step towards the observation of proton dynamics in real space and time.
View details for DOI 10.1103/PhysRevLett.131.143001
View details for PubMedID 37862660
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Time-Resolved X-ray Photoelectron Spectroscopy: Ultrafast Dynamics in CS2 Probed at the S 2p Edge.
The journal of physical chemistry letters
2023: 7126-7133
Abstract
Recent developments in X-ray free-electron lasers have enabled a novel site-selective probe of coupled nuclear and electronic dynamics in photoexcited molecules, time-resolved X-ray photoelectron spectroscopy (TRXPS). We present results from a joint experimental and theoretical TRXPS study of the well-characterized ultraviolet photodissociation of CS2, a prototypical system for understanding non-adiabatic dynamics. These results demonstrate that the sulfur 2p binding energy is sensitive to changes in the nuclear structure following photoexcitation, which ultimately leads to dissociation into CS and S photoproducts. We are able to assign the main X-ray spectroscopic features to the CS and S products via comparison to a first-principles determination of the TRXPS based on ab initio multiple-spawning simulations. Our results demonstrate the use of TRXPS as a local probe of complex ultrafast photodissociation dynamics involving multimodal vibrational coupling, nonradiative transitions between electronic states, and multiple final product channels.
View details for DOI 10.1021/acs.jpclett.3c01447
View details for PubMedID 37534743
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Femtosecond pulse parameter estimation from photoelectron momenta using machine learning
NEW JOURNAL OF PHYSICS
2023; 25 (8)
View details for DOI 10.1088/1367-2630/acee19
View details for Web of Science ID 001114342100001
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Filming enhanced ionization in an ultrafast triatomic slingshot.
Communications chemistry
2023; 6 (1): 81
Abstract
Filming atomic motion within molecules is an active pursuit of molecular physics and quantum chemistry. A promising method is laser-induced Coulomb Explosion Imaging (CEI) where a laser pulse rapidly ionizes many electrons from a molecule, causing the remaining ions to undergo Coulomb repulsion. The ion momenta are used to reconstruct the molecular geometry which is tracked over time (i.e., filmed) by ionizing at an adjustable delay with respect to the start of interatomic motion. Results are distorted, however, by ultrafast motion during the ionizing pulse. We studied this effect in water and filmed the rapid "slingshot" motion that enhances ionization and distorts CEI results. Our investigation uncovered both the geometry and mechanism of the enhancement which may inform CEI experiments in many other polyatomic molecules.
View details for DOI 10.1038/s42004-023-00882-w
View details for PubMedID 37106058
View details for PubMedCentralID PMC10140156
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Multiparticle Cumulant Mapping for Coulomb Explosion Imaging.
Physical review letters
2023; 130 (9): 093001
Abstract
We extend covariance velocity map ion imaging to four particles, establishing cumulant mapping and allowing for measurements that provide insights usually associated with coincidence detection, but at much higher count rates. Without correction, a fourfold covariance analysis is contaminated by the pairwise correlations of uncorrelated events, but we have addressed this with the calculation of a full cumulant, which subtracts pairwise correlations. We demonstrate the approach on the four-body breakup of formaldehyde following strong field multiple ionization in few-cycle laser pulses. We compare Coulomb explosion imaging for two different pulse durations (30 and 6 fs), highlighting the dynamics that can take place on ultrafast timescales. These results have important implications for Coulomb explosion imaging as a tool for studying ultrafast structural changes in molecules, a capability that is especially desirable for high-count-rate x-ray free-electron laser experiments.
View details for DOI 10.1103/PhysRevLett.130.093001
View details for PubMedID 36930921
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Photon energy-resolved velocity map imaging from spectral domain ghost imaging
NEW JOURNAL OF PHYSICS
2023; 25 (3)
View details for DOI 10.1088/1367-2630/acc201
View details for Web of Science ID 000956244500001
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Transient vibration and product formation of photoexcited CS2 measured by time-resolved x-ray scattering.
The Journal of chemical physics
2022; 157 (16): 164305
Abstract
We have observed details of the internal motion and dissociation channels in photoexcited carbon disulfide (CS2) using time-resolved x-ray scattering (TRXS). Photoexcitation of gas-phase CS2 with a 200nm laser pulse launches oscillatory bending and stretching motion, leading to dissociation of atomic sulfur in under a picosecond. During the first 300fs following excitation, we observe significant changes in the vibrational frequency as well as some dissociation of the C-S bond, leading to atomic sulfur in the both 1D and 3P states. Beyond 1400fs, the dissociation is consistent with primarily 3P atomic sulfur dissociation. This channel-resolved measurement of the dissociation time is based on our analysis of the time-windowed dissociation radial velocity distribution, which is measured using the temporal Fourier transform of the TRXS data aided by a Hough transform that extracts the slopes of linear features in an image. The relative strength of the two dissociation channels reflects both their branching ratio and differences in the spread of their dissociation times. Measuring the time-resolved dissociation radial velocity distribution aids the resolution of discrepancies between models for dissociation proposed by prior photoelectron spectroscopy work.
View details for DOI 10.1063/5.0113079
View details for PubMedID 36319419
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Probing two-path electron quantum interference in strong-field ionization with time-correlation filtering
PHYSICAL REVIEW A
2022; 106 (3)
View details for DOI 10.1103/PhysRevA.106.033118
View details for Web of Science ID 000870237400004
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Disentangling sequential and concerted fragmentations of molecular polycations with covariant native frame analysis.
Physical chemistry chemical physics : PCCP
2022
Abstract
We present results from an experimental ion imaging study into the fragmentation dynamics of 1-iodopropane and 2-iodopropane following interaction with extreme ultraviolet intense femtosecond laser pulses with a photon energy of 95 eV. Using covariance imaging analysis, a range of observed fragmentation pathways of the resulting polycations can be isolated and interrogated in detail at relatively high ion count rates (12 ions shot-1). By incorporating the recently developed native frames analysis approach into the three-dimensional covariance imaging procedure, contributions from three-body concerted and sequential fragmentation mechanisms can be isolated. The angular distribution of the fragment ions is much more complex than in previously reported studies for triatomic polycations, and differs substantially between the two isomeric species. With support of simple simulations of the dissociation channels of interest, detailed physical insights into the fragmentation dynamics are obtained, including how the initial dissociation step in a sequential mechanism influences rovibrational dynamics in the metastable intermediate ion and how signatures of this nuclear motion manifest in the measured signals.
View details for DOI 10.1039/d2cp03029b
View details for PubMedID 36106844
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Multichannel photodissociation dynamics in CS2 studied by ultrafast electron diffraction.
Physical chemistry chemical physics : PCCP
2022
Abstract
The structural dynamics of photoexcited gas-phase carbon disulfide (CS2) molecules are investigated using ultrafast electron diffraction. The dynamics were triggered by excitation of the optically bright 1B2(1Sigmau+) state by an ultraviolet femtosecond laser pulse centred at 200 nm. In accordance with previous studies, rapid vibrational motion facilitates a combination of internal conversion and intersystem crossing to lower-lying electronic states. Photodissociation via these electronic manifolds results in the production of CS fragments in the electronic ground state and dissociated singlet and triplet sulphur atoms. The structural dynamics are extracted from the experiment using a trajectory-fitting filtering approach, revealing the main characteristics of the singlet and triplet dissociation pathways. Finally, the effect of the time-resolution on the experimental signal is considered and an outlook to future experiments provided.
View details for DOI 10.1039/d2cp01268e
View details for PubMedID 35707953
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Attosecond coherent electron motion in Auger-Meitner decay.
Science (New York, N.Y.)
1800: eabj2096
Abstract
[Figure: see text].
View details for DOI 10.1126/science.abj2096
View details for PubMedID 34990213
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Role of nuclear-electronic coupling in attosecond photoionization of H-2
PHYSICAL REVIEW A
2021; 104 (6)
View details for DOI 10.1103/PhysRevA.104.063119
View details for Web of Science ID 000737281100001
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Multi-Particle Three-Dimensional Covariance Imaging: "Coincidence" Insights into the Many-Body Fragmentation of Strong-Field Ionized D2O.
The journal of physical chemistry letters
2021: 8302-8308
Abstract
We demonstrate the applicability of covariance analysis to three-dimensional velocity-map imaging experiments using a fast time stamping detector. Studying the photofragmentation of strong-field doubly ionized D2O molecules, we show that combining high count rate measurements with covariance analysis yields the same level of information typically limited to the "gold standard" of true, low count rate coincidence experiments, when averaging over a large ensemble of photofragmentation events. This increases the effective data acquisition rate by approximately 2 orders of magnitude, enabling a new class of experimental studies. This is illustrated through an investigation into the dependence of three-body D2O2+ dissociation on the intensity of the ionizing laser, revealing mechanistic insights into the nuclear dynamics driven during the laser pulse. The experimental methodology laid out, with its drastic reduction in acquisition time, is expected to be of great benefit to future photofragment imaging studies.
View details for DOI 10.1021/acs.jpclett.1c02481
View details for PubMedID 34428066
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Strong-field ionization of water. II. Electronic and nuclear dynamics en route to double ionization
PHYSICAL REVIEW A
2021; 104 (2)
View details for DOI 10.1103/PhysRevA.104.023108
View details for Web of Science ID 000688095500011
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Dissecting subcycle interference in photoelectron holography
PHYSICAL REVIEW A
2021; 104 (1)
View details for DOI 10.1103/PhysRevA.104.013109
View details for Web of Science ID 000675546200009
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Disentangling the subcycle electron momentum spectrum in strong-field ionization
PHYSICAL REVIEW RESEARCH
2021; 3 (2)
View details for DOI 10.1103/PhysRevResearch.3.023065
View details for Web of Science ID 000643687200002
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Multi-channel photodissociation and XUV-induced charge transfer dynamics in strong-field-ionized methyl iodide studied with time-resolved recoil-frame covariance imaging.
Faraday discussions
2021
Abstract
The photodissociation dynamics of strong-field ionized methyl iodide (CH3I) were probed using intense extreme ultraviolet (XUV) radiation produced by the SPring-8 Angstrom Compact free electron LAser (SACLA). Strong-field ionization and subsequent fragmentation of CH3I was initiated by an intense femtosecond infrared (IR) pulse. The ensuing fragmentation and charge transfer processes following multiple ionization by the XUV pulse at a range of pump-probe delays were followed in a multi-mass ion velocity-map imaging (VMI) experiment. Simultaneous imaging of a wide range of resultant ions allowed for additional insight into the complex dynamics by elucidating correlations between the momenta of different fragment ions using time-resolved recoil-frame covariance imaging analysis. The comprehensive picture of the photodynamics that can be extracted provides promising evidence that the techniques described here could be applied to study ultrafast photochemistry in a range of molecular systems at high count rates using state-of-the-art advanced light sources.
View details for DOI 10.1039/d0fd00115e
View details for PubMedID 33629700
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Resolving multiphoton processes with high-order anisotropy ultrafast X-ray scattering.
Faraday discussions
2021
Abstract
We present the first results on experimentally measured ultrafast X-ray scattering of strongly driven molecular iodine and analysis of high-order anisotropic components of the scattering signal. We discuss the technical details of retrieving high fidelity high-order anisotropy components from the measured scattering data and outline a method to analyze such signals using Legendre decomposition. We describe how anisotropic motions can be extracted from the various Legendre orders using simulated anisotropic scattering signals and Fourier analysis. We implement the method on the measured signal and observe a multitude of dissociation and vibration motions simultaneously arising from various multiphoton transitions occurring in the sample. We use the anisotropic scattering information to disentangle the different processes and assign their dissociation velocities on the Angstrom and femtosecond scales de novo.
View details for DOI 10.1039/d0fd00126k
View details for PubMedID 33565543
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X-ray scattering signatures of early-time accelerations in iodine dissociation
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2020; 53 (24)
View details for DOI 10.1088/1361-6455/abc22a
View details for Web of Science ID 000590718800001
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Time-resolved site-selective imaging of predissociation and charge transfer dynamics: the CH3I B-band
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2020; 53 (22)
View details for DOI 10.1088/1361-6455/abb1fd
View details for Web of Science ID 000581546500001
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Momentum-resolved above-threshold ionization of deuterated water
PHYSICAL REVIEW A
2020; 102 (5)
View details for DOI 10.1103/PhysRevA.102.052813
View details for Web of Science ID 000589620200002
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Beating absorption in solid-state high harmonics
COMMUNICATIONS PHYSICS
2020; 3 (1)
View details for DOI 10.1038/s42005-020-00472-5
View details for Web of Science ID 000588103100005
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Electron correlation effects in attosecond photoionization of CO2
PHYSICAL REVIEW A
2020; 102 (2)
View details for DOI 10.1103/PhysRevA.102.023118
View details for Web of Science ID 000565703000005
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Electronic Population Transfer via Impulsive Stimulated X-Ray Raman Scattering with Attosecond Soft-X-Ray Pulses.
Physical review letters
2020; 125 (7): 073203
Abstract
Free-electron lasers provide a source of x-ray pulses short enough and intense enough to drive nonlinearities in molecular systems. Impulsive interactions driven by these x-ray pulses provide a way to create and probe valence electron motions with high temporal and spatial resolution. Observing these electronic motions is crucial to understand the role of electronic coherence in chemical processes. A simple nonlinear technique for probing electronic motion, impulsive stimulated x-ray Raman scattering (ISXRS), involves a single impulsive interaction to produce a coherent superposition of electronic states. We demonstrate electronic population transfer via ISXRS using broad bandwidth (5.5 eV full width at half maximum) attosecond x-ray pulses produced by the Linac Coherent Light Source. The impulsive excitation is resonantly enhanced by the oxygen 1s→2π^{*} resonance of nitric oxide (NO), and excited state neutral molecules are probed with a time-delayed UV laser pulse.
View details for DOI 10.1103/PhysRevLett.125.073203
View details for PubMedID 32857563
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Electronic Population Transfer via Impulsive Stimulated X-Ray Raman Scattering with Attosecond Soft-X-Ray Pulses
PHYSICAL REVIEW LETTERS
2020; 125 (7)
View details for DOI 10.1103/PhysRevLett.125.073203
View details for Web of Science ID 000558086800003
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Ionization induced dynamic alignment of water.
The Journal of chemical physics
2020; 152 (13): 134308
Abstract
Two-body dissociation resulting from strong-field double ionization of water is investigated. Two distinct features are seen in the alignment of the fragment momenta with respect to the laser polarization. One feature shows alignment of the H-OH axis with the laser polarization, while the other indicates polarization alignment normal to the H-OH axis. By analyzing kinematic differences between the OH+/D+ and OD+/H+ channels of HOD, these two alignment features are shown to result from dissociation from different states in the dication. Only dissociation from one of these states has an alignment dependence consistent with predictions of sequential strong-field tunneling ionization models. The alignment dependence of dissociation from the other state can only be explained by dynamic alignment launched by the unbending of the molecule during ionization.
View details for DOI 10.1063/5.0002877
View details for PubMedID 32268745
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Characterizing Multiphoton Excitation Using Time-Resolved X-ray Scattering
PHYSICAL REVIEW X
2020; 10 (1)
View details for DOI 10.1103/PhysRevX.10.011065
View details for Web of Science ID 000519993700001
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X-ray diffractive imaging of controlled gas-phase molecules: Toward imaging of dynamics in the molecular frame.
The Journal of chemical physics
2020; 152 (8): 084307
Abstract
We report experimental results on the diffractive imaging of three-dimensionally aligned 2,5-diiodothiophene molecules. The molecules were aligned by chirped near-infrared laser pulses, and their structure was probed at a photon energy of 9.5 keV (lambda 130 pm) provided by the Linac Coherent Light Source. Diffracted photons were recorded on the Cornell-SLAC pixel array detector, and a two-dimensional diffraction pattern of the equilibrium structure of 2,5-diiodothiophene was recorded. The retrieved distance between the two iodine atoms agrees with the quantum-chemically calculated molecular structure to be within 5%. The experimental approach allows for the imaging of intrinsic molecular dynamics in the molecular frame, albeit this requires more experimental data, which should be readily available at upcoming high-repetition-rate facilities.
View details for DOI 10.1063/1.5133963
View details for PubMedID 32113333
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Tunable isolated attosecond X-ray pulses with gigawatt peak power from a free-electron laser
NATURE PHOTONICS
2020; 14 (1): 30-+
View details for DOI 10.1038/s41566-019-0549-5
View details for Web of Science ID 000504727600007
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Strictly non-adiabatic quantum control of the acetylene dication using an infrared field.
The Journal of chemical physics
2020; 152 (18): 184302
Abstract
We demonstrate the existence of a strictly non-adiabatic control pathway in deprotonation of the acetylene dication. This pathway is identified experimentally by measuring a kinetic energy shift in an ion coincidence experiment. We use a time dependent Schrödinger equation simulation to identify which properties most strongly affect our control. We find that resonant control around conical intersections is limited by the speed of non-adiabatic dynamics.
View details for DOI 10.1063/5.0007058
View details for PubMedID 32414271
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Attosecond transient absorption spooktroscopy: a ghost imaging approach to ultrafast absorption spectroscopy.
Physical chemistry chemical physics : PCCP
2019
Abstract
The recent demonstration of isolated attosecond pulses from an X-ray free-electron laser (XFEL) opens the possibility for probing ultrafast electron dynamics at X-ray wavelengths. An established experimental method for probing ultrafast dynamics is X-ray transient absorption spectroscopy, where the X-ray absorption spectrum is measured by scanning the central photon energy and recording the resultant photoproducts. The spectral bandwidth inherent to attosecond pulses is wide compared to the resonant features typically probed, which generally precludes the application of this technique in the attosecond regime. In this paper we propose and demonstrate a new technique to conduct transient absorption spectroscopy with broad bandwidth attosecond pulses with the aid of ghost imaging, recovering sub-bandwidth resolution in photoproduct-based absorption measurements.
View details for DOI 10.1039/c9cp03951a
View details for PubMedID 31793561
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Characterizing dissociative motion in time-resolved x-ray scattering from gas-phase diatomic molecules
PHYSICAL REVIEW A
2019; 100 (3)
View details for DOI 10.1103/PhysRevA.100.033413
View details for Web of Science ID 000486625200003
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On the limits of observing motion in time-resolved X-ray scattering
PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES
2019; 377 (2145)
View details for DOI 10.1098/rsta.2017.0477
View details for Web of Science ID 000465499800010
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On the limits of observing motion in time-resolved X-ray scattering.
Philosophical transactions. Series A, Mathematical, physical, and engineering sciences
2019; 377 (2145): 20170477
Abstract
Limits on the ability of time-resolved X-ray scattering (TRXS) to observe harmonic motion of amplitude, A and frequency, omega0, about an equilibrium position, R0, are considered. Experimental results from a TRXS experiment at the LINAC Coherent Light Source are compared to classical and quantum theories that demonstrate a fundamental limitation on the ability to observe the amplitude of motion. These comparisons demonstrate dual limits on the spatial resolution through Qmax and the temporal resolution through omegamax for observing the amplitude of motion. In the limit where omegamax omega0, the smallest observable amplitude of motion is A=2 pi/ Qmax. In the limit where omegamax≥2 omega0, A≤2 pi/ Qmax is observable provided there are sufficient statistics. This article is part of the theme issue 'Measurement of ultrafast electronic and structural dynamics with X-rays'.
View details for PubMedID 30929636
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Characterization of high-harmonic emission from ZnO up to 11 eV pumped with a Cr:ZnS high-repetition-rate source
OPTICS LETTERS
2019; 44 (2): 259–62
Abstract
We report the measurement of high-order harmonics from a ZnO crystal with photon energies up to 11 eV generated by a high-repetition-rate femtosecond Cr:ZnS laser operating in the mid-infrared at 2-3 μm, delivering few-cycle pulses with multi-watt average power and multi-megawatt peak power. High-focus intensity is achieved in a single pass through the crystal without a buildup cavity or nanostructued pattern for field enhancement. We measure in excess of 108 high-harmonic photons/second.
View details for DOI 10.1364/OL.44.000259
View details for Web of Science ID 000455620100020
View details for PubMedID 30644875
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Generation and Characterization of Attosecond Pulses from an X-ray Free-electron Laser
IEEE. 2019
View details for Web of Science ID 000482226301273
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Enhanced high-harmonic generation from an all-dielectric metasurface
NATURE PHYSICS
2018; 14 (10): 1006-+
View details for DOI 10.1038/s41567-018-0233-6
View details for Web of Science ID 000446186700013
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Roadmap of ultrafast x-ray atomic and molecular physics
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2018; 51 (3)
View details for DOI 10.1088/1361-6455/aa9735
View details for Web of Science ID 000419798100001
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Accurate prediction of X-ray pulse properties from a free-electron laser using machine learning.
Nature communications
2017; 8: 15461-?
Abstract
Free-electron lasers providing ultra-short high-brightness pulses of X-ray radiation have great potential for a wide impact on science, and are a critical element for unravelling the structural dynamics of matter. To fully harness this potential, we must accurately know the X-ray properties: intensity, spectrum and temporal profile. Owing to the inherent fluctuations in free-electron lasers, this mandates a full characterization of the properties for each and every pulse. While diagnostics of these properties exist, they are often invasive and many cannot operate at a high-repetition rate. Here, we present a technique for circumventing this limitation. Employing a machine learning strategy, we can accurately predict X-ray properties for every shot using only parameters that are easily recorded at high-repetition rate, by training a model on a small set of fully diagnosed pulses. This opens the door to fully realizing the promise of next-generation high-repetition rate X-ray lasers.
View details for DOI 10.1038/ncomms15461
View details for PubMedID 28580940
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Strong Field Double-Ionization of Water
IEEE. 2017
View details for Web of Science ID 000427296201120
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Coherent control using kinetic energy and the geometric phase of a conical intersection.
journal of chemical physics
2016; 145 (14): 144304-?
Abstract
Conical intersections (CIs) between molecular potential energy surfaces with non-vanishing non-adiabatic couplings generally occur in any molecule consisting of at least three atoms. They play a fundamental role in describing the molecular dynamics beyond the Born-Oppenheimer approximation and have been used to understand a large variety of effects, from photofragmentation and isomerization to more exotic applications such as exciton fission in semiconductors. However, few studies have used the features of a CI as a tool for coherent control. Here we demonstrate two modes of control around a conical intersection. The first uses a continuous light field to control the population on the two intersecting electronic states in the vicinity of a CI. The second uses a pulsed light field to control wavepackets that are subjected to the geometric phase shift in transit around a CI. This second technique is likely to be useful for studying the role of nuclear dynamics in electronic coherence phenomena.
View details for PubMedID 27782506
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Self-Referenced Coherent Diffraction X-Ray Movie of Angstrom- and Femtosecond-Scale Atomic Motion
PHYSICAL REVIEW LETTERS
2016; 117 (15)
Abstract
Time-resolved femtosecond x-ray diffraction patterns from laser-excited molecular iodine are used to create a movie of intramolecular motion with a temporal and spatial resolution of 30 fs and 0.3 Å. This high fidelity is due to interference between the nonstationary excitation and the stationary initial charge distribution. The initial state is used as the local oscillator for heterodyne amplification of the excited charge distribution to retrieve real-space movies of atomic motion on ångstrom and femtosecond scales. This x-ray interference has not been employed to image internal motion in molecules before. Coherent vibrational motion and dispersion, dissociation, and rotational dephasing are all clearly visible in the data, thereby demonstrating the stunning sensitivity of heterodyne methods.
View details for DOI 10.1103/PhysRevLett.117.153003
View details for Web of Science ID 000384479300005
View details for PubMedID 27768351
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Observation of Quantum Interferences via Light-Induced Conical Intersections in Diatomic Molecules
PHYSICAL REVIEW LETTERS
2016; 116 (14)
Abstract
We observe energy-dependent angle-resolved diffraction patterns in protons from strong-field dissociation of the molecular hydrogen ion H_{2}^{+}. The interference is a characteristic of dissociation around a laser-induced conical intersection (LICI), which is a point of contact between two surfaces in the dressed two-dimensional Born-Oppenheimer potential energy landscape of a diatomic molecule in a strong laser field. The interference magnitude and angular period depend strongly on the energy difference between the initial state and the LICI, consistent with coherent diffraction around a cone-shaped potential barrier whose width and thickness depend on the relative energy of the initial state and the cone apex. These findings are supported by numerical solutions of the time-dependent Schrödinger equation for similar experimental conditions.
View details for DOI 10.1103/PhysRevLett.116.143004
View details for Web of Science ID 000373587500007
View details for PubMedID 27104704
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Collisional decoherence and rotational quasirevivals in asymmetric-top molecules
PHYSICAL REVIEW A
2016; 93 (1)
View details for DOI 10.1103/PhysRevA.93.013421
View details for Web of Science ID 000368983200011
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Femtosecond X-ray-induced fragmentation of fullerenes
JOURNAL OF MODERN OPTICS
2016; 63 (4): 390-401
View details for DOI 10.1080/09500340.2015.1064175
View details for Web of Science ID 000369083600010
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Transient lattice contraction in the solid-to-plasma transition.
Science advances
2016; 2 (1)
Abstract
In condensed matter systems, strong optical excitations can induce phonon-driven processes that alter their mechanical properties. We report on a new phenomenon where a massive electronic excitation induces a collective change in the bond character that leads to transient lattice contraction. Single large van der Waals clusters were isochorically heated to a nanoplasma state with an intense 10-fs x-ray (pump) pulse. The structural evolution of the nanoplasma was probed with a second intense x-ray (probe) pulse, showing systematic contraction stemming from electron delocalization during the solid-to-plasma transition. These findings are relevant for any material in extreme conditions ranging from the time evolution of warm or hot dense matter to ultrafast imaging with intense x-ray pulses or, more generally, any situation that involves a condensed matter-to-plasma transition.
View details for DOI 10.1126/sciadv.1500837
View details for PubMedID 27152323
View details for PubMedCentralID PMC4846449
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Auger electron and photoabsorption spectra of glycine in the vicinity of the oxygen K-edge measured with an X-FEL
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2015; 48 (23)
View details for DOI 10.1088/0953-4075/48/23/234004
View details for Web of Science ID 000365240900005
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Observation of Bloch Oscillations in Molecular Rotation
PHYSICAL REVIEW LETTERS
2015; 115 (20)
View details for DOI 10.1103/PhysRevLett.115.203002
View details for Web of Science ID 000364415000003
View details for PubMedID 26613436
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Anomalous nonlinear X-ray Compton scattering
NATURE PHYSICS
2015; 11 (11): 964-970
View details for DOI 10.1038/NPHYS3452
View details for Web of Science ID 000364800600023
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Strongly aligned gas-phase molecules at free-electron lasers
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2015; 48 (20)
View details for DOI 10.1088/0953-4075/48/20/204002
View details for Web of Science ID 000362421800004
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Ab initio multiple spawning on laser-dressed states: a study of 1,3-cyclohexadiene photoisomerization via light-induced conical intersections
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2015; 48 (16)
View details for DOI 10.1088/0953-4075/48/16/164003
View details for Web of Science ID 000358623500003
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Dynamical localization in molecular alignment of kicked quantum rotors
PHYSICAL REVIEW A
2015; 92 (1)
View details for DOI 10.1103/PhysRevA.92.013409
View details for Web of Science ID 000357854100012
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BRIGHTER AND FASTER The promise and challenge of the x-ray free-electron laser
PHYSICS TODAY
2015; 68 (7): 26-32
View details for DOI 10.1063/PT.3.2845
View details for Web of Science ID 000360924700015
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Transient Impulsive Electronic Raman Redistribution
PHYSICAL REVIEW LETTERS
2015; 114 (14)
Abstract
Resonant Raman excitation by ultrafast vacuum ultraviolet laser pulses is a powerful means to study electron dynamics in molecules, but experiments must contend with linear background ionization: frequencies high enough to reach resonant core-valence transitions will usually ionize all occupied orbitals as well, and the ionization cross sections are usually dominant. Here we show that attosecond pulses can induce a process, transient impulsive stimulated Raman scattering, which can overwhelm valence ionization. Calculations are performed for atomic sodium, but the principal is valid for many molecular systems. This approach opens the path for high-fidelity multidimensional spectroscopy with attosecond pulses.
View details for DOI 10.1103/PhysRevLett.114.143005
View details for Web of Science ID 000352688000002
View details for PubMedID 25910119
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Ultrafast isomerization initiated by X-ray core ionization.
Nature communications
2015; 6: 8199-?
Abstract
Rapid proton migration is a key process in hydrocarbon photochemistry. Charge migration and subsequent proton motion can mitigate radiation damage when heavier atoms absorb X-rays. If rapid enough, this can improve the fidelity of diffract-before-destroy measurements of biomolecular structure at X-ray-free electron lasers. Here we study X-ray-initiated isomerization of acetylene, a model for proton dynamics in hydrocarbons. Our time-resolved measurements capture the transient motion of protons following X-ray ionization of carbon K-shell electrons. We Coulomb-explode the molecule with a second precisely delayed X-ray pulse and then record all the fragment momenta. These snapshots at different delays are combined into a 'molecular movie' of the evolving molecule, which shows substantial proton redistribution within the first 12 fs. We conclude that significant proton motion occurs on a timescale comparable to the Auger relaxation that refills the K-shell vacancy.
View details for DOI 10.1038/ncomms9199
View details for PubMedID 26354002
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Ultrafast isomerization initiated by X-ray core ionization.
Nature communications
2015; 6: 8199-?
View details for DOI 10.1038/ncomms9199
View details for PubMedID 26354002
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Probing electron delays in above-threshold ionization
OPTICA
2014; 1 (6): 361-364
View details for DOI 10.1364/OPTICA.1.000361
View details for Web of Science ID 000354864400001
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Remote two-color optical-to-optical synchronization between two passively mode-locked lasers
OPTICS LETTERS
2014; 39 (18): 5325-5328
View details for DOI 10.1364/OL.39.005325
View details for Web of Science ID 000341926500022
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Probing ultrafast electronic and molecular dynamics with free-electron lasers
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2014; 47 (12)
View details for DOI 10.1088/0953-4075/47/12/124006
View details for Web of Science ID 000337721200007
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Ultrafast X-ray Auger probing of photoexcited molecular dynamics
NATURE COMMUNICATIONS
2014; 5
View details for DOI 10.1038/ncomms5235
View details for Web of Science ID 000338840000004
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Axis-dependence of molecular high harmonic emission in three dimensions.
Nature communications
2014; 5: 3190-?
Abstract
High-order harmonic generation in an atomic or molecular gas is a promising source of sub-femtosecond vacuum ultraviolet coherent radiation for transient scattering, absorption, metrology and imaging applications. High harmonic spectra are sensitive to Ångstrom-scale structure and motion of laser-driven molecules, but interference from radiation produced by random molecular orientations obscures this in all but the simplest cases, such as linear molecules. Here we show how to extract full body-frame high harmonic generation information for molecules with more complicated geometries by utilizing the methods of coherent transient rotational spectroscopy. To demonstrate this approach, we obtain the relative strength of harmonic emission along the three principal axes in the asymmetric-top sulphur dioxide. This greatly simplifies the analysis task of high harmonic spectroscopy and extends its usefulness to more complex molecules.
View details for DOI 10.1038/ncomms4190
View details for PubMedID 24504181
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THE ULTIMATE X-RAY MACHINE
SCIENTIFIC AMERICAN
2014; 310 (1): 64-71
View details for Web of Science ID 000328864500034
View details for PubMedID 24616973
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Ultrafast X-ray Auger probing of photoexcited molecular dynamics.
Nature communications
2014; 5: 4235-?
Abstract
Molecules can efficiently and selectively convert light energy into other degrees of freedom. Disentangling the underlying ultrafast motion of electrons and nuclei of the photoexcited molecule presents a challenge to current spectroscopic approaches. Here we explore the photoexcited dynamics of molecules by an interaction with an ultrafast X-ray pulse creating a highly localized core hole that decays via Auger emission. We discover that the Auger spectrum as a function of photoexcitation--X-ray-probe delay contains valuable information about the nuclear and electronic degrees of freedom from an element-specific point of view. For the nucleobase thymine, the oxygen Auger spectrum shifts towards high kinetic energies, resulting from a particular C-O bond stretch in the ππ* photoexcited state. A subsequent shift of the Auger spectrum towards lower kinetic energies displays the electronic relaxation of the initial photoexcited state within 200 fs. Ab-initio simulations reinforce our interpretation and indicate an electronic decay to the nπ* state.
View details for DOI 10.1038/ncomms5235
View details for PubMedID 24953740
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Experimental strategies for optical pump - soft x-ray probe experiments at the LCLS
28th International Conference on Photonic, Electronic and Atomic Collisions (ICPEAC)
IOP PUBLISHING LTD. 2014
View details for DOI 10.1088/1742-6596/488/1/012015
View details for Web of Science ID 000338432500015
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Toward unsupervised single-shot diffractive imaging of heterogeneous particles using X-ray free-electron lasers
OPTICS EXPRESS
2013; 21 (23): 28729-28742
Abstract
Single shot diffraction imaging experiments via X-ray free-electron lasers can generate as many as hundreds of thousands of diffraction patterns of scattering objects. Recovering the real space contrast of a scattering object from these patterns currently requires a reconstruction process with user guidance in a number of steps, introducing severe bottlenecks in data processing. We present a series of measures that replace user guidance with algorithms that reconstruct contrasts in an unsupervised fashion. We demonstrate the feasibility of automating the reconstruction process by generating hundreds of contrasts obtained from soot particle diffraction experiments.
View details for DOI 10.1364/OE.21.028729
View details for Web of Science ID 000327494000115
View details for PubMedID 24514385
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Enhancement of strong-field multiple ionization in the vicinity of the conical intersection in 1,3-cyclohexadiene ring opening
JOURNAL OF CHEMICAL PHYSICS
2013; 139 (18)
Abstract
Nonradiative energy dissipation in electronically excited polyatomic molecules proceeds through conical intersections, loci of degeneracy between electronic states. We observe a marked enhancement of laser-induced double ionization in the vicinity of a conical intersection during a non-radiative transition. We measured double ionization by detecting the kinetic energy of ions released by laser-induced strong-field fragmentation during the ring-opening transition between 1,3-cyclohexadiene and 1,3,5-hexatriene. The enhancement of the double ionization correlates with the conical intersection between the HOMO and LUMO orbitals.
View details for DOI 10.1063/1.4829766
View details for Web of Science ID 000327712800032
View details for PubMedID 24320276
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Mesoscale morphology of airborne core-shell nanoparticle clusters: x-ray laser coherent diffraction imaging
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2013; 46 (16)
View details for DOI 10.1088/0953-4075/46/16/164033
View details for Web of Science ID 000323113100034
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Ultra-fast and ultra-intense x-ray sciences: first results from the Linac Coherent Light Source free-electron laser
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2013; 46 (16)
View details for DOI 10.1088/0953-4075/46/16/164003
View details for Web of Science ID 000323113100004
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Sensing the wavefront of x-ray free-electron lasers using aerosol spheres
OPTICS EXPRESS
2013; 21 (10): 12385-12394
Abstract
Characterizing intense, focused x-ray free electron laser (FEL) pulses is crucial for their use in diffractive imaging. We describe how the distribution of average phase tilts and intensities on hard x-ray pulses with peak intensities of 10(21) W/m(2) can be retrieved from an ensemble of diffraction patterns produced by 70 nm-radius polystyrene spheres, in a manner that mimics wavefront sensors. Besides showing that an adaptive geometric correction may be necessary for diffraction data from randomly injected sample sources, our paper demonstrates the possibility of collecting statistics on structured pulses using only the diffraction patterns they generate and highlights the imperative to study its impact on single-particle diffractive imaging.
View details for DOI 10.1364/OE.21.012385
View details for Web of Science ID 000319339600072
View details for PubMedID 23736456
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On the possibility of enhanced multiple ionization near conical intersections
FARADAY DISCUSSIONS
2013; 163: 475-484
View details for DOI 10.1039/c3fd20154f
View details for Web of Science ID 000322120500024
- Ultrafast quantum control in atoms and molecules, Ultrafast nonlinear optics Ultrafast quantum control in atoms and molecules, Ultrafast nonlinear optics 2013: 105 - 128
- Review: Atoms in intense laser fields. 2013: 49
- Femtosecond fiber timing distribution system for the linac coherent light source 2013
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Probing nucleobase photoprotection with soft x-rays
18th International Conference on Ultrafast Phenomena
E D P SCIENCES. 2013
View details for DOI 10.1051/epjconf/20134107004
View details for Web of Science ID 000320558600179
- Ultrafast amo physics at the lcls x-ray fel EPJ Web of Conferences 2013
- Probing nucleobase photoprotection with soft x-ray EPJ Web of Conferences 2013
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Multiphoton Ionization as a clock to Reveal Molecular Dynamics with Intense Short X-ray Free Electron Laser Pulses
PHYSICAL REVIEW LETTERS
2012; 109 (26)
Abstract
We investigate molecular dynamics of multiple ionization in N2 through multiple core-level photoabsorption and subsequent Auger decay processes induced by intense, short x-ray free electron laser pulses. The timing dynamics of the photoabsorption and dissociation processes is mapped onto the kinetic energy of the fragments. Measurements of the latter allow us to map out the average internuclear separation for every molecular photoionization sequence step and obtain the average time interval between the photoabsorption events. Using multiphoton ionization as a tool of the multiple-pulse pump-probe scheme, we demonstrate the modification of the ionization dynamics as we vary the x-ray laser pulse duration.
View details for DOI 10.1103/PhysRevLett.109.263001
View details for Web of Science ID 000312846800008
View details for PubMedID 23368555
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Fractal morphology, imaging and mass spectrometry of single aerosol particles in flight
NATURE
2012; 486 (7404): 513-517
Abstract
The morphology of micrometre-size particulate matter is of critical importance in fields ranging from toxicology to climate science, yet these properties are surprisingly difficult to measure in the particles' native environment. Electron microscopy requires collection of particles on a substrate; visible light scattering provides insufficient resolution; and X-ray synchrotron studies have been limited to ensembles of particles. Here we demonstrate an in situ method for imaging individual sub-micrometre particles to nanometre resolution in their native environment, using intense, coherent X-ray pulses from the Linac Coherent Light Source free-electron laser. We introduced individual aerosol particles into the pulsed X-ray beam, which is sufficiently intense that diffraction from individual particles can be measured for morphological analysis. At the same time, ion fragments ejected from the beam were analysed using mass spectrometry, to determine the composition of single aerosol particles. Our results show the extent of internal dilation symmetry of individual soot particles subject to non-equilibrium aggregation, and the surprisingly large variability in their fractal dimensions. More broadly, our methods can be extended to resolve both static and dynamic morphology of general ensembles of disordered particles. Such general morphology has implications in topics such as solvent accessibilities in proteins, vibrational energy transfer by the hydrodynamic interaction of amino acids, and large-scale production of nanoscale structures by flame synthesis.
View details for DOI 10.1038/nature11222
View details for Web of Science ID 000305760600039
View details for PubMedID 22739316
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Transient X-Ray Fragmentation: Probing a Prototypical Photoinduced Ring Opening
PHYSICAL REVIEW LETTERS
2012; 108 (25)
Abstract
We report the first study of UV-induced photoisomerization probed via core ionization by an x-ray laser. We investigated x-ray ionization and fragmentation of the cyclohexadiene-hexatriene system at 850 eV during the ring opening. We find that the ion-fragmentation patterns evolve over a picosecond, reflecting a change in the state of excitation and the molecular geometry: the average kinetic energy per ion fragment and H(+)-ion count increase as the ring opens and the molecule elongates. We discuss new opportunities for molecular photophysics created by optical pump x-ray probe experiments.
View details for DOI 10.1103/PhysRevLett.108.253006
View details for Web of Science ID 000305569100005
View details for PubMedID 23004597
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Ultrafast absorption of intense x rays by nitrogen molecules
JOURNAL OF CHEMICAL PHYSICS
2012; 136 (21)
Abstract
We devise a theoretical description for the response of nitrogen molecules (N(2)) to ultrashort and intense x rays from the free electron laser Linac Coherent Light Source (LCLS). We set out from a rate-equation description for the x-ray absorption by a nitrogen atom. The equations are formulated using all one-x-ray-photon absorption cross sections and the Auger and radiative decay widths of multiply-ionized nitrogen atoms. Cross sections are obtained with a one-electron theory and decay widths are determined from ab initio computations using the Dirac-Hartree-Slater (DHS) method. We also calculate all binding and transition energies of nitrogen atoms in all charge states with the DHS method as the difference of two self-consistent field (SCF) calculations (ΔSCF method). To describe the interaction with N(2), a detailed investigation of intense x-ray-induced ionization and molecular fragmentation are carried out. As a figure of merit, we calculate ion yields and the average charge state measured in recent experiments at the LCLS. We use a series of phenomenological models of increasing sophistication to unravel the mechanisms of the interaction of x rays with N(2): a single atom, a symmetric-sharing model, and a fragmentation-matrix model are developed. The role of the formation and decay of single and double core holes, the metastable states of N(2)(2+), and molecular fragmentation are explained.
View details for DOI 10.1063/1.4722756
View details for Web of Science ID 000305090900028
View details for PubMedID 22697546
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Control of 1,3-Cyclohexadiene Photoisomerization Using Light-Induced Conical Intersections
JOURNAL OF PHYSICAL CHEMISTRY A
2012; 116 (11): 2758-2763
Abstract
We have studied the photoinduced isomerization from 1,3-cyclohexadiene to 1,3,5-hexatriene in the presence of an intense ultrafast laser pulse. We find that the laser field maximally suppresses isomerization if it is both polarized parallel to the excitation dipole and present 50 fs after the initial photoabsorption, at the time when the system is expected to be in the vicinity of a conical intersection that mediates this structural transition. A modified ab initio multiple spawning (AIMS) method shows that the laser induces a resonant coupling between the excited state and the ground state, i.e., a light-induced conical intersection. The theory accounts for the timing and direction of the effect.
View details for DOI 10.1021/jp208384b
View details for Web of Science ID 000301766500022
View details for PubMedID 22082319
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Molecular frame Auger electron energy spectrum from N-2
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2012; 45 (5)
View details for DOI 10.1088/0953-4075/45/5/055601
View details for Web of Science ID 000300707800011
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Ultrafast ring opening in 1,3-cyclohexadiene investigated by simplex-based spectral unmixing
JOURNAL OF CHEMICAL PHYSICS
2012; 136 (5)
Abstract
We use spectral unmixing to determine the number of transient photoproducts and to track their evolution following the photo-excitation of 1,3-cyclohexadiene (CHD) to form 1,3,5-hexatriene (HT) in the gas phase. The ring opening is initiated with a 266 nm ultraviolet laser pulse and probed via fragmentation with a delayed intense infrared 800 nm laser pulse. The ion time-of-flight (TOF) spectra are analyzed with a simplex-based spectral unmixing technique. We find that at least three independent spectra are needed to model the transient TOF spectra. Guided by mathematical and physical constraints, we decompose the transient TOF spectra into three spectra associated with the presence of CHD, CHD(+), and HT, and show how these three species appear at different times during the ring opening.
View details for DOI 10.1063/1.3681258
View details for Web of Science ID 000300547200020
View details for PubMedID 22320738
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Field-Free Asymmetric Top Alignment and Rotational Revivals Using High Harmonic Generation
Conference on Lasers and Electro-Optics (CLEO)
IEEE. 2012
View details for Web of Science ID 000310362400040
- Quantified angular contributions for high harmonic emission of molecules in three dimensions physics.atom-ph 2012; arXiv:1207.2517v1
- Ultrafast nucleobase photoprotection probed by soft x-rays 2012
- Measuring 10 fs dynamics via resonant x-ray pump/x-ray probe spectroscopy DAMOP 2012
- Ultrafast nucleobase photoprotection probed by soft x-rays Laser Science 2012
- High harmonic probes of inner electron sub-cycle dynamics in molecules 2012
- Femtosecond dynamics of ultraviolet photoprotection in Thymine Banff Meeting on Structural Dynamics 2012
- Studying nucleobase photoprotection with soft x-rays Ultrafast Phenomena 2012
- Profiling structured beams using injected aerosols 2012
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Ultrafast X-ray probe of Nucleobase Photoprotection
Conference on Lasers and Electro-Optics (CLEO)
IEEE. 2012
View details for Web of Science ID 000310362403286
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Sub-Cycle Strong-Field Influences in X-ray Photoionization
Conference on Lasers and Electro-Optics (CLEO)
IEEE. 2012
View details for Web of Science ID 000310362403285
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Unveiling and Driving Hidden Resonances with High-Fluence, High-Intensity X-Ray Pulses
PHYSICAL REVIEW LETTERS
2011; 107 (23)
Abstract
We show that high fluence, high-intensity x-ray pulses from the world's first hard x-ray free-electron laser produce nonlinear phenomena that differ dramatically from the linear x-ray-matter interaction processes that are encountered at synchrotron x-ray sources. We use intense x-ray pulses of sub-10-fs duration to first reveal and subsequently drive the 1s↔2p resonance in singly ionized neon. This photon-driven cycling of an inner-shell electron modifies the Auger decay process, as evidenced by line shape modification. Our work demonstrates the propensity of high-fluence, femtosecond x-ray pulses to alter the target within a single pulse, i.e., to unveil hidden resonances, by cracking open inner shells energetically inaccessible via single-photon absorption, and to consequently trigger damaging electron cascades at unexpectedly low photon energies.
View details for DOI 10.1103/PhysRevLett.107.233001
View details for Web of Science ID 000297501900007
View details for PubMedID 22182083
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Teravolt-per-meter beam and plasma fields from low-charge femtosecond electron beams
4th International Conference on Superstrong Fields in Plasmas
ELSEVIER SCIENCE BV. 2011: 98–102
View details for DOI 10.1016/j.nima.2011.01.073
View details for Web of Science ID 000295663800021
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Strong Field Ionization to Multiple Electronic States in Water
PHYSICAL REVIEW LETTERS
2011; 107 (8)
Abstract
High harmonic spectra show that laser-induced strong field ionization of water has a significant contribution from an inner-valence orbital. Our experiment uses the ratio of H(2)O and D(2)O high harmonic yields to isolate the characteristic nuclear motion of the molecular ionic states. The nuclear motion initiated via ionization of the highest occupied molecular orbital (HOMO) is small and is expected to lead to similar harmonic yields for the two isotopes. In contrast, ionization of the second least bound orbital (HOMO-1) exhibits itself via a strong bending motion which creates a significant isotope effect. We elaborate on this interpretation by solving the time-dependent Schrödinger equation to simulate strong field ionization and high harmonic generation from the water isotopes. We expect that this isotope marking scheme for probing excited ionic states in strong field processes can be generalized to other molecules.
View details for DOI 10.1103/PhysRevLett.107.083001
View details for Web of Science ID 000293977000008
View details for PubMedID 21929165
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Ensemble of Linear Molecules in Nondispersing Rotational Quantum States: A Molecular Stopwatch
PHYSICAL REVIEW X
2011; 1 (1)
View details for DOI 10.1103/PhysRevX.1.011002
View details for Web of Science ID 000310504700002
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Influence of phase matching on the Cooper minimum in Ar high-order harmonic spectra
PHYSICAL REVIEW A
2011; 83 (2)
View details for DOI 10.1103/PhysRevA.83.023420
View details for Web of Science ID 000287728100010
- Angular Dependance of Auger electrons from N$_{2}$ 42nd Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics 2011: L1.00144
- The First Atomic and Molecular Experiments at the Linac Coherent Light Source X-Ray Free Electron Laser Advances In Atomic, Molecular, and Optical Physics. Chapter 5 - Academic Press. edited by Arimondo, E., Berman, P. R., Lin, C. C. 2011
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Single particle imaging with soft X-rays at the Linac Coherent Light Source
Conference on Advances in X-ray Free-Electron Lasers - Radiation Schemes, X-ray Optics, and Instrumentation
SPIE-INT SOC OPTICAL ENGINEERING. 2011
View details for DOI 10.1117/12.886754
View details for Web of Science ID 000293180500004
- Nonlinear atomic response to intense, ultrashort x rays 42nd Annual Meeting of the APS Division of Atomic, Molecular and Optical Physics 2011: L1.00060
- Influence of Phase Matching of the Cooper Minimum in Argon High Harmonic Spectra CLEO/QELS Abstracts 2011
- Isotope effect in the high harmonics of water Bull. Am. Phys. Soc. 2011
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First lasing and operation of an angstrom-wavelength free-electron laser
NATURE PHOTONICS
2010; 4 (9): 641-647
View details for DOI 10.1038/NPHOTON.2010.176
View details for Web of Science ID 000281467900020
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Double Core-Hole Production in N-2: Beating the Auger Clock
PHYSICAL REVIEW LETTERS
2010; 105 (8)
Abstract
We investigate the creation of double K-shell holes in N2 molecules via sequential absorption of two photons on a time scale shorter than the core-hole lifetime by using intense x-ray pulses from the Linac Coherent Light Source free electron laser. The production and decay of these states is characterized by photoelectron spectroscopy and Auger electron spectroscopy. In molecules, two types of double core holes are expected, the first with two core holes on the same N atom, and the second with one core hole on each N atom. We report the first direct observations of the former type of core hole in a molecule, in good agreement with theory, and provide an experimental upper bound for the relative contribution of the latter type.
View details for DOI 10.1103/PhysRevLett.105.083005
View details for Web of Science ID 000281072100004
View details for PubMedID 20868097
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Auger Electron Angular Distribution of Double Core-Hole States in the Molecular Reference Frame
PHYSICAL REVIEW LETTERS
2010; 105 (8)
Abstract
The Linac Coherent Light Source free electron laser is a source of high brightness x rays, 2×10(11) photons in a ∼5 fs pulse, that can be focused to produce double core vacancies through rapid sequential ionization. This enables double core vacancy Auger electron spectroscopy, an entirely new way to study femtosecond chemical dynamics with Auger electrons that probe the local valence structure of molecules near a specific atomic core. Using 1.1 keV photons for sequential x-ray ionization of impulsively aligned molecular nitrogen, we observed a rich single-site double core vacancy Auger electron spectrum near 413 eV, in good agreement with ab initio calculations, and we measured the corresponding Auger electron angle dependence in the molecular frame.
View details for DOI 10.1103/PhysRevLett.105.083004
View details for Web of Science ID 000281072100003
View details for PubMedID 20868096
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Time-resolved pump-probe experiments at the LCLS
OPTICS EXPRESS
2010; 18 (17): 17620-17630
Abstract
The first time-resolved x-ray/optical pump-probe experiments at the SLAC Linac Coherent Light Source (LCLS) used a combination of feedback methods and post-analysis binning techniques to synchronize an ultrafast optical laser to the linac-based x-ray laser. Transient molecular nitrogen alignment revival features were resolved in time-dependent x-ray-induced fragmentation spectra. These alignment features were used to find the temporal overlap of the pump and probe pulses. The strong-field dissociation of x-ray generated quasi-bound molecular dications was used to establish the residual timing jitter. This analysis shows that the relative arrival time of the Ti:Sapphire laser and the x-ray pulses had a distribution with a standard deviation of approximately 120 fs. The largest contribution to the jitter noise spectrum was the locking of the laser oscillator to the reference RF of the accelerator, which suggests that simple technical improvements could reduce the jitter to better than 50 fs.
View details for Web of Science ID 000281054400005
View details for PubMedID 20721148
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Femtosecond electronic response of atoms to ultra-intense X-rays
NATURE
2010; 466 (7302): 56-U66
Abstract
An era of exploring the interactions of high-intensity, hard X-rays with matter has begun with the start-up of a hard-X-ray free-electron laser, the Linac Coherent Light Source (LCLS). Understanding how electrons in matter respond to ultra-intense X-ray radiation is essential for all applications. Here we reveal the nature of the electronic response in a free atom to unprecedented high-intensity, short-wavelength, high-fluence radiation (respectively 10(18) W cm(-2), 1.5-0.6 nm, approximately 10(5) X-ray photons per A(2)). At this fluence, the neon target inevitably changes during the course of a single femtosecond-duration X-ray pulse-by sequentially ejecting electrons-to produce fully-stripped neon through absorption of six photons. Rapid photoejection of inner-shell electrons produces 'hollow' atoms and an intensity-induced X-ray transparency. Such transparency, due to the presence of inner-shell vacancies, can be induced in all atomic, molecular and condensed matter systems at high intensity. Quantitative comparison with theory allows us to extract LCLS fluence and pulse duration. Our successful modelling of X-ray/atom interactions using a straightforward rate equation approach augurs favourably for extension to complex systems.
View details for DOI 10.1038/nature09177
View details for Web of Science ID 000279343800034
View details for PubMedID 20596013
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Ultraintense X-Ray Induced Ionization, Dissociation, and Frustrated Absorption in Molecular Nitrogen
PHYSICAL REVIEW LETTERS
2010; 104 (25)
Abstract
Sequential multiple photoionization of the prototypical molecule N2 is studied with femtosecond time resolution using the Linac Coherent Light Source (LCLS). A detailed picture of intense x-ray induced ionization and dissociation dynamics is revealed, including a molecular mechanism of frustrated absorption that suppresses the formation of high charge states at short pulse durations. The inverse scaling of the average target charge state with x-ray peak brightness has possible implications for single-pulse imaging applications.
View details for DOI 10.1103/PhysRevLett.104.253002
View details for Web of Science ID 000279174700002
View details for PubMedID 20867372
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Strongly dispersive transient Bragg grating for high harmonics
OPTICS LETTERS
2010; 35 (12): 2028-2030
Abstract
We create a transient Bragg grating in a high-harmonic generation medium using two counterpropagating pulses. The Bragg grating disperses the harmonics in angle and can diffract a large bandwidth with temporal resolution limited only by the source size.
View details for Web of Science ID 000279435800034
View details for PubMedID 20548375
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Calibration of a high harmonic spectrometer by laser induced plasma emission
Conference on Lasers and Electro-Optics (CLEO)/Quantum Electronics and Laser Science Conference (QELS)
IEEE. 2010
View details for Web of Science ID 000290513602211
- Formation and Dissociation of Transient Molecular States with Ultrafast X Rays DAMOP 2010
- Ultrafast strong field xray interactions with aligned molecules at LCLS DAMOP 2010
- Angular Dependance of Auger Decay of Double Core Vacancies in N$_{2}$ DAMOP 2010
- Strong field Multiphoton processes in the high-frequency limit DAMOP 2010
- Characterization of LCLS X-Ray Pulses Using Atomic Spectroscopy DAMOP 2010
- The atomic response to 10$^{18}$ W/cm$^2$ x-rays from the LCLS DAMOP 2010
- Bragg Diffraction High Harmonic Spectroscopy DAMOP 2010
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Nonlinear processes in N-2 using LCLS short x-ray pulses
Conference on Lasers and Electro-Optics (CLEO)/Quantum Electronics and Laser Science Conference (QELS)
IEEE. 2010
View details for Web of Science ID 000290513602041
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Ultrafast X-ray-Pump, Laser-Probe Spectroscopy at LCLS
Conference on Lasers and Electro-Optics (CLEO)/Quantum Electronics and Laser Science Conference (QELS)
IEEE. 2010
View details for Web of Science ID 000290513602040
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Xray-Induced Multiple Core Vacancies in Impulsively Aligned Molecules
Conference on Lasers and Electro-Optics (CLEO)/Quantum Electronics and Laser Science Conference (QELS)
IEEE. 2010
View details for Web of Science ID 000290513602039
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High Harmonic Transient Grating Spectroscopy
Conference on Lasers and Electro-Optics (CLEO)/Quantum Electronics and Laser Science Conference (QELS)
IEEE. 2010
View details for Web of Science ID 000290513601109
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Breaking the Attosecond, Angstrom and TV/m Field Barriers with Ultrafast Electron Beams
14th Workshop on Advanced Accelerator Concepts
AMER INST PHYSICS. 2010: 489–494
View details for Web of Science ID 000287176200081
- High Harmonic Generation in Sulfur Dioxide DAMOP 2010
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Relation of high harmonic spectra to electronic structure in N-2
CHEMICAL PHYSICS
2009; 366 (1-3): 15-21
View details for DOI 10.1016/j.chemphys.2009.10.015
View details for Web of Science ID 000272205000004
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Field-free alignment in repetitively kicked nitrogen gas
PHYSICAL REVIEW A
2009; 80 (6)
View details for DOI 10.1103/PhysRevA.80.063412
View details for Web of Science ID 000273233800111
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High-order harmonic phase in molecular nitrogen
PHYSICAL REVIEW A
2009; 80 (3)
View details for DOI 10.1103/PhysRevA.80.033412
View details for Web of Science ID 000270383900121
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Calibration of a high harmonic spectrometer by laser induced plasma emission
OPTICS EXPRESS
2009; 17 (17): 15134-15144
Abstract
We present a method that allows for a convenient switching between high harmonic generation (HHG) and accurate calibration of the vacuum ultraviolet (VUV) spectrometer used to analyze the harmonic spectrum. The accurate calibration of HHG spectra is becoming increasingly important for the determination of electronic structures. The wavelength of the laser harmonics themselves depend on the details of the harmonic geometry and phase matching, making them unsuitable for calibration purposes. In our calibration mode, the target resides directly at the focus of the laser, thereby enhancing plasma emission and suppressing harmonic generation. In HHG mode, the source medium resides in front or after the focus, showing enhanced HHG and no plasma emission lines. We analyze the plasma emission and use it for a direct calibration of our HHG spectra.
View details for Web of Science ID 000269232800068
View details for PubMedID 19687991
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Single-Shot Diffractive Imaging with a Table-Top Femtosecond Soft X-Ray Laser-Harmonics Source
PHYSICAL REVIEW LETTERS
2009; 103 (2)
Abstract
Coherent x-ray diffractive imaging is a powerful method for studies on nonperiodic structures on the nanoscale. Access to femtosecond dynamics in major physical, chemical, and biological processes requires single-shot diffraction data. Up to now, this has been limited to intense coherent pulses from a free electron laser. Here we show that laser-driven ultrashort x-ray sources offer a comparatively inexpensive alternative. We present measurements of single-shot diffraction patterns from isolated nano-objects with a single 20 fs pulse from a table-top high-harmonic x-ray laser. Images were reconstructed with a resolution of 119 nm from the single shot and 62 nm from multiple shots.
View details for DOI 10.1103/PhysRevLett.103.028104
View details for Web of Science ID 000267887800065
View details for PubMedID 19659250
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Control of retinal isomerization in bacteriorhodopsin in the high-intensity regime
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
2009; 106 (27): 10896-10900
Abstract
A learning algorithm was used to manipulate optical pulse shapes and optimize retinal isomerization in bacteriorhodopsin, for excitation levels up to 1.8 x 10(16) photons per square centimeter. Below 1/3 the maximum excitation level, the yield was not sensitive to pulse shape. Above this level the learning algorithm found that a Fourier-transform-limited (TL) pulse maximized the 13-cis population. For this optimal pulse the yield increases linearly with intensity well beyond the saturation of the first excited state. To understand these results we performed systematic searches varying the chirp and energy of the pump pulses while monitoring the isomerization yield. The results are interpreted including the influence of 1-photon and multiphoton transitions. The population dynamics in each intermediate conformation and the final branching ratio between the all-trans and 13-cis isomers are modified by changes in the pulse energy and duration.
View details for DOI 10.1073/pnas.0904589106
View details for Web of Science ID 000267796100007
View details for PubMedID 19564608
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Generation of attosecond x-ray pulses with a multicycle two-color enhanced self-amplified spontaneous emission scheme
PHYSICAL REVIEW SPECIAL TOPICS-ACCELERATORS AND BEAMS
2009; 12 (6)
View details for DOI 10.1103/PhysRevSTAB.12.060703
View details for Web of Science ID 000267763000004
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AMO Experiments at the LCLS X-ray Laser
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2009)
IEEE. 2009: 3191–3192
View details for Web of Science ID 000274751302581
- Origin of the Spectral Minimum in the High Harmonics of N2 2009: JTuD33
- Rotational decoherence in a dense gas of multiply kicked N2 2009: B6.2
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Coherent Control of Retinal Isomerization in Bacteriorhodopsin in the High Intensity Regime
16th International Conference on Ultrafast Phenomena
SPRINGER-VERLAG BERLIN. 2009: 430–432
View details for Web of Science ID 000282108000139
- Strong field Cooper minimum in High Harmonic Generation 2009: S5.04
- Impulsive Alignment of N2with a Train of 8 Pulses IQEC Abstracts 2009: pp.IWB1.
- High Degrees of Impulsive Alignment in Repetitively Excited N2 at STP 2009: Q5.09.
- AMO Research at the LCLS X-Ray Laser IQEC Abstract 2009: JWB1.
- Angular and Intensity Dependent Spectral Modulations in High Harmonics from N2 2009: Y1.00032.
- Impulsive longitudinal molecular alignment 2009: B6.04
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Impulsive alignment of N-2 with a train of 8 pulses
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2009)
IEEE. 2009: 2381–2382
View details for Web of Science ID 000274751302174
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High harmonic generation from multiple molecular orbitals
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2009)
IEEE. 2009: 2511–2512
View details for Web of Science ID 000274751302240
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High Harmonic Generation from Multiple Orbitals in N-2
SCIENCE
2008; 322 (5905): 1232-1235
Abstract
Molecular electronic states energetically below the highest occupied molecular orbital (HOMO) should contribute to laser-driven high harmonic generation (HHG), but this behavior has not been observed previously. Our measurements of the HHG spectrum of N2 molecules aligned perpendicular to the laser polarization showed a maximum at the rotational half-revival. This feature indicates the influence of electrons occupying the orbital just below the N2 HOMO, referred to as the HOMO-1. Such observations of lower-lying orbitals are essential to understanding subfemtosecond/subangstrom electronic motion in laser-excited molecules.
View details for DOI 10.1126/science.1162780
View details for Web of Science ID 000261033400037
View details for PubMedID 18974318
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Strong-field impulsive alignment in the presence of high temperatures and large centrifugal distortion
PHYSICAL REVIEW A
2008; 78 (3)
View details for DOI 10.1103/PhysRevA.78.035401
View details for Web of Science ID 000259689400212
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Multiphoton control of the 1,3-cyclohexadiene ring-opening reaction in the presence of competing solvent reactions
JOURNAL OF PHYSICAL CHEMISTRY A
2008; 112 (30): 6811-6822
Abstract
Although physical chemistry has often concentrated on the observation and understanding of chemical systems, the defining characteristic of chemistry remains the direction and control of chemical reactivity. Optical control of molecular dynamics, and thus of chemical reactivity provides a path to use photon energy as a smart reagent in a chemical system. In this paper, we discuss recent research in this field in the context of our studies of the multiphoton optical control of the photo-initiated ring-opening reaction of 1,3-cyclohexadiene (CHD) to form 1,3,5- cis-hexatriene (Z-HT). Closed-loop feedback and learning algorithms are able to identify pulses that increase the desired target state by as much as a factor of two. Mechanisms for control are discussed through the influence of the intensity dependence, the nonlinear power spectrum, and the projection of the pulses onto low orders of polynomial phase. Control measurements in neat solvents demonstrate that competing solvent fragmentation reactions must also be considered. In particular, multiphoton excitation of cyclohexane alone is capable of producing hexatriene. Statistical analyses of data sets obtained in learning algorithm searches in neat cyclohexane and for CHD in hexane and cyclohexane highlight the importance of linear and quadratic chirp, while demonstrating that the control features are not so easily defined. Higher order phase components are also important. On the basis of these results the involvement of low-frequency ground-state vibrational modes is proposed. When the population is transferred to the excited state, momentum along the torsional coordinate may keep the wave packet localized as it moves toward the conical intersections controlling the yield of Z-HT.
View details for DOI 10.1021/jp8013404
View details for Web of Science ID 000257926900006
View details for PubMedID 18593101
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Phase control of the competition between electronic transitions in a solvated laser dye
8th International Conference on Femtochemistry and Femtobiology
ELSEVIER SCIENCE BV. 2008: 75–86
View details for DOI 10.1016/j.chemphys.2008.01.023
View details for Web of Science ID 000257539500010
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X-ray diffuse scattering measurements of nucleation dynamics at femtosecond resolution
PHYSICAL REVIEW LETTERS
2008; 100 (13)
Abstract
Femtosecond time-resolved small and wide angle x-ray diffuse scattering techniques are applied to investigate the ultrafast nucleation processes that occur during the ablation process in semiconducting materials. Following intense optical excitation, a transient liquid state of high compressibility characterized by large-amplitude density fluctuations is observed and the buildup of these fluctuations is measured in real time. Small-angle scattering measurements reveal snapshots of the spontaneous nucleation of nanoscale voids within a metastable liquid and support theoretical predictions of the ablation process.
View details for DOI 10.1103/PhysRevLett.100.135502
View details for Web of Science ID 000254670300046
View details for PubMedID 18517965
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Formation of secondary electron cascades in single-crystalline plasma-deposited diamond upon exposure to femtosecond x-ray pulses
JOURNAL OF APPLIED PHYSICS
2008; 103 (6)
View details for DOI 10.1063/1.2890158
View details for Web of Science ID 000254536900143
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Probing Excited State Dynamics of Retinal Isomerization in Bacteriorhodopsin
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2008)
IEEE. 2008: 2509–2510
View details for Web of Science ID 000260498401245
- Observation of an Intensity Dependent Minimum and Harmonic Dependent Linewidths in the High Harmonic Spectrum of Nitrogen QELS 2008
- Orientation of ``asymmetric-top'' water molecules with shaped terahertz fields DAMOP 2008
- Strong field impulsive alignment in the presence of high temperatures and large centrifugal distortion DAMOP 2008
- High harmonic generation from multiple molecular orbitals of N2 Ultrafast Phenomena XV 2008
- Intensity Dependent Interference Structures in High Harmonic Generation DAMOP 2008
- HOMO-1 Contribution in High Harmonic Generation DAMOP 2008
- Coherent Control of Retinal Isomerization in Bacteriorhodopsin in the High Intensity Regime DAMOP 2008
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High Harmonic Spectral Minimum and Phase in Argon and Nitrogen
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2008)
IEEE. 2008: 3181–3182
View details for Web of Science ID 000260498401584
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Observation of an Intensity Dependent Minimum and Harmonic Dependent Linewidths in the High Harmonic Spectrum of N-2
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2008)
IEEE. 2008: 2679–2680
View details for Web of Science ID 000260498401330
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Impulsive Alignment of Hot, Centrifugally Distorted, Molecules
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference (CLEO/QELS 2008)
IEEE. 2008: 1770–1771
View details for Web of Science ID 000260498400888
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High harmonic generation for N-2 and CO2 beyond the two-point model
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2007; 40 (18): 3745-3755
View details for DOI 10.1088/0953-4075/40/18/013
View details for Web of Science ID 000249864600015
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The future of attosecond Spectroscopy
SCIENCE
2007; 317 (5839): 766-769
Abstract
Attoscience is the study of physical processes that occur in less than a fraction of a cycle of visible light, in times less than a quadrillionth of a second. The motion of electrons inside atoms and molecules that are undergoing photoionization or chemical change falls within this time scale, as does the plasma motion that causes the reflectivity of metals. The techniques to study motion on this scale are based on careful control of strong-field laser-atom interactions. These techniques and new research opportunities in attosecond spectroscopy are reviewed.
View details for DOI 10.1126/science.1142135
View details for Web of Science ID 000248624500029
View details for PubMedID 17690285
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Carrier-density-dependent lattice stability in InSb
PHYSICAL REVIEW LETTERS
2007; 98 (12)
Abstract
The ultrafast decay of the x-ray diffraction intensity following laser excitation of an InSb crystal has been utilized to observe carrier dependent changes in the potential energy surface. For the first time, an abrupt carrier dependent onset for potential energy surface softening and the appearance of accelerated atomic disordering for a very high average carrier density have been observed. Inertial dynamics dominate the early stages of crystal disordering for a wide range of carrier densities between the onset of crystal softening and the appearance of accelerated atomic disordering.
View details for DOI 10.1103/PhysRevLett.98.125501
View details for PubMedID 17501133
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Ultrafast bond softening in bismuth: Mapping a solid's interatomic potential with X-rays
SCIENCE
2007; 315 (5812): 633-636
Abstract
Intense femtosecond laser excitation can produce transient states of matter that would otherwise be inaccessible to laboratory investigation. At high excitation densities, the interatomic forces that bind solids and determine many of their properties can be substantially altered. Here, we present the detailed mapping of the carrier density-dependent interatomic potential of bismuth approaching a solid-solid phase transition. Our experiments combine stroboscopic techniques that use a high-brightness linear electron accelerator-based x-ray source with pulse-by-pulse timing reconstruction for femtosecond resolution, allowing quantitative characterization of the interatomic potential energy surface of the highly excited solid.
View details for DOI 10.1126/science.1135009
View details for Web of Science ID 000243909400039
View details for PubMedID 17272718
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Mechanistic Comparison of Different Solutions Found in Closed-Loop Quantum Control Simulations
Conference on Lasers and Electro-Optics/Quantum Electronics and Laser Science Conference
IEEE. 2007: 2486–2487
View details for Web of Science ID 000268751001692
- Ultrafast X-ray Science at SLAC and LCLS March APS Meeting 2007
- Mechanistic Comparison of Different Solutions Found in Closed-Loop Quantum Control Simulations CLEO/QELS 2007
- Rotational wave packets probed by high harmonic generation DAMOP 2007
- High harmonic generation for N2 and CO2 beyond the two-point model At. Mol. Opt. Phys 2007
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Control of 1,3-cyclohexadiene ring-opening
15th International Conference on Ultrafast Phenomena
SPRINGER-VERLAG BERLIN. 2007: 249–251
View details for Web of Science ID 000250104700080
- Direct Dissociation and Laser Modulated Predissociation of N2 CLEO/QELS 2007
- High Harmonic Imaging of Conical Intersections QTuE6 2007
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Ultrafast x-ray science at SLAC: Preparing for LCLS
15th International Conference on Atomic Processes in Plasmas
AMER INST PHYSICS. 2007: 3–3
View details for Web of Science ID 000249095400001
- High Harmonic Imaging of Conical Intersections DAMOP 2007
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Optical control of excited-state vibrational coherences of a molecule in solution: The influence of the excitation pulse spectrum and phase in LD690
JOURNAL OF PHYSICAL CHEMISTRY B
2006; 110 (40): 20023-20031
Abstract
Spectral and phase shaping of femtosecond laser pulses is used to selectively excite vibrational wave packets on the ground (S0) and excited (S1) electronic states in the laser dye LD690. The transient absorption signals observed following excitation near the peak of the ground-state absorption spectrum are characterized by a dominant 586 cm(-1) vibrational mode. This vibration is assigned to a wave packet on the S0 potential energy surface. When the excitation pulse is tuned to the blue wing of the absorption spectrum, a lower frequency 568 cm(-1) vibration dominates the response. This lower frequency mode is assigned to a vibrational wave packet on the S1 electronic state. The spectrum and phase of the excitation pulse also influence both the dephasing of the vibrational wave packet and the amplitude profiles of the oscillations as a function of probe wavelength. Excitation by blue-tuned, positively chirped pulses slows the apparent dephasing of the vibrational coherences compared with a transform-limited pulse having the same spectrum. Blue-tuned negatively chirped excitation pulses suppress the observation of coherent oscillations in the ground state.
View details for DOI 10.1021/jp0627628
View details for Web of Science ID 000241053400035
View details for PubMedID 17020390
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Information hiding and retrieval in Rydberg wave packets using half-cycle pulses
PHYSICAL REVIEW A
2006; 74 (4)
View details for DOI 10.1103/PhysRevA.74.043402
View details for Web of Science ID 000241723100115
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Photon science and quantum control
PHYSICS TODAY
2006; 59 (6): 57-59
View details for Web of Science ID 000238076100029
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Observing angular precession of a Rydberg wave packet due to spin-orbit coupling by orthogonally polarized weak half-cycle pulses
PHYSICAL REVIEW A
2006; 73 (5)
View details for DOI 10.1103/PhysRevA.73.052504
View details for Web of Science ID 000237949300062
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The first femtosecond in the life of a chemical reaction
SCIENCE
2006; 312 (5772): 373-374
View details for DOI 10.1126/science.1125514
View details for Web of Science ID 000236941800028
View details for PubMedID 16627727
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Spectral phase effects on nonlinear resonant photochemistry of 1,3-cyclohexadiene in solution
JOURNAL OF CHEMICAL PHYSICS
2006; 124 (11)
Abstract
We have investigated the ring opening of 1,3-cyclohexadiene to form 1,3,5-cis-hexatriene (Z-HT) using optical pulse shaping to enhance multiphoton excitation. A closed-loop learning algorithm was used to search for an optimal spectral phase function, with the effectiveness or fitness of each optical pulse assessed using the UV absorption spectrum. The learning algorithm was able to identify pulses that increased the formation of Z-HT by as much as a factor of 2 and to identify pulse shapes that decreased solvent fragmentation while leaving the formation of Z-HT essentially unaffected. The highest yields of Z-HT did not occur for the highest peak intensity laser pulses. Rather, negative quadratic phase was identified as an important control parameter in the formation of Z-HT.
View details for DOI 10.1063/1.2168454
View details for Web of Science ID 000236160000034
View details for PubMedID 16555900
- Learning Feedback Control Analysis Proceedings of Femtochemistry. 2006
- Coherent control of excited state vibrational coherences of a molecule in solution DAMOP 2006
- Controlling the Quantum World of Atoms, Molecules, and Photons Washington: National Academies Press. 2006
- Quantum Control ICOLS proceedings 2006
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On the search for quantum control of electronic spin by shaped ultrafast optical pulses
1st International Conference on Quantum Computing - Back Action
AMER INST PHYSICS. 2006: 295–300
View details for Web of Science ID 000243789900027
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Simulations of the phonon Bragg switch in GaAs
SOLID STATE COMMUNICATIONS
2005; 136 (3): 181-185
View details for DOI 10.1016/j.sse.2005.05.056
View details for Web of Science ID 000232175300011
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Observation of structural anisotropy and the onset of liquidlike motion during the nonthermal melting of InSb
PHYSICAL REVIEW LETTERS
2005; 95 (12)
Abstract
The melting dynamics of laser excited InSb have been studied with femtosecond x-ray diffraction. These measurements observe the delayed onset of diffusive atomic motion, signaling the appearance of liquidlike dynamics. They also demonstrate that the root-mean-squared displacement in the [111] direction increases faster than in the [110] direction after the first 500 fs. This structural anisotropy indicates that the initially generated fluid differs significantly from the equilibrium liquid.
View details for DOI 10.1103/PhysRevLett.95.125701
View details for Web of Science ID 000231908200033
View details for PubMedID 16197085
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Atomic-scale visualization of inertial dynamics
SCIENCE
2005; 308 (5720): 392-395
Abstract
The motion of atoms on interatomic potential energy surfaces is fundamental to the dynamics of liquids and solids. An accelerator-based source of femtosecond x-ray pulses allowed us to follow directly atomic displacements on an optically modified energy landscape, leading eventually to the transition from crystalline solid to disordered liquid. We show that, to first order in time, the dynamics are inertial, and we place constraints on the shape and curvature of the transition-state potential energy surface. Our measurements point toward analogies between this nonequilibrium phase transition and the short-time dynamics intrinsic to equilibrium liquids.
View details for DOI 10.1126/science.1107996
View details for Web of Science ID 000228492000046
View details for PubMedID 15831753
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Clocking femtosecond x rays
PHYSICAL REVIEW LETTERS
2005; 94 (11)
Abstract
Linear-accelerator-based sources will revolutionize ultrafast x-ray science due to their unprecedented brightness and short pulse duration. However, time-resolved studies at the resolution of the x-ray pulse duration are hampered by the inability to precisely synchronize an external laser to the accelerator. At the Sub-Picosecond Pulse Source at the Stanford Linear-Accelerator Center we solved this problem by measuring the arrival time of each high energy electron bunch with electro-optic sampling. This measurement indirectly determined the arrival time of each x-ray pulse relative to an external pump laser pulse with a time resolution of better than 60 fs rms.
View details for DOI 10.1103/PhysRevLett.94.114801
View details for Web of Science ID 000227923200034
View details for PubMedID 15903864
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X-ray synchrotron studies of ultrafast crystalline dynamics
Symposium on Applications of Synchrotron Radiation to Materials
WILEY-BLACKWELL. 2005: 177–192
Abstract
Ultrafast X-ray experiments at synchrotron sources hold tremendous promise for measuring the atomistic dynamics of materials under a wide variety of transient conditions. In particular, the marriage of synchrotron radiation and ultrafast laser technology is opening up a new frontier of materials research. Structural changes initiated by femtosecond laser pulses can be tracked in real time using time-resolved X-ray diffraction on picosecond time scales or shorter. Here, research at the Advanced Photon Source is described, illustrating the opportunities for ultrafast diffraction with some recent work on the generation of impulsive strain, coherent phonon generation and supersonic diffusion of electron-hole plasmas. The flexibility of time-resolved Bragg and Laue diffraction geometries are both utilized to illuminate the strain generation and evolution process. Time-resolved X-ray science will become increasingly important with the construction of linac-based ultrafast X-ray sources.
View details for DOI 10.1107/S0909049504033679
View details for Web of Science ID 000227377200008
View details for PubMedID 15728970
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Coherence measurements on Rydberg wave packets kicked by a half-cycle pulse
PHYSICAL REVIEW A
2005; 71 (2)
View details for DOI 10.1103/PhysRevA.71.023408
View details for Web of Science ID 000227483900083
- High-efficiency phase-shaped ultra-broadband non-collinear optical parametric amplifier (NOPA) DAMOP 2005
- Spectrally Resolved Transient Alignment of Molecular Iodine DAMOP 2005
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Probing the evolution of Stark wave packets by a weak half-cycle pulse
PHYSICAL REVIEW A
2005; 71 (1)
View details for DOI 10.1103/PhysRevA.71.013407
View details for Web of Science ID 000227283300104
- Controlling the Quantum World of Atoms, Molecules, and Photons An Interim Report Washington: National Academies Press. 2005
- Coherence measurement of kicked Rydberg wave packets DAMOP 2005
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Extracting quantum dynamics from genetic learning algorithms through principal control analysis
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
2004; 37 (24): L399-L405
View details for DOI 10.1088/0953-4075/37/24/L02
View details for Web of Science ID 000227580900002
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X-ray movies of wiggling crystals
SCIENCE
2004; 306 (5702): 1691-1692
View details for DOI 10.1126/science.1106755
View details for Web of Science ID 000225630800029
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On the role of coupling in mode selective excitation using ultrafast pulse shaping in stimulated Raman spectroscopy
JOURNAL OF CHEMICAL PHYSICS
2004; 121 (8): 3434-3437
Abstract
The coherence of two coupled two-level systems, representing vibrational modes in a semiclassical model, is calculated in weak and strong fields for various coupling schemes and for different relative phases between initial state amplitudes. A relative phase equal to pi projects the system into a dark state. The selective excitation of one of the two, two-level systems is studied as a function of coupling strength and initial phases.
View details for DOI 10.1063/1.1774985
View details for Web of Science ID 000223234200010
View details for PubMedID 15303906
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Ultrafast x-ray physics
Indo/United States Workshop on Radiation Physics with Synchrotrons and Other New Sources
PERGAMON-ELSEVIER SCIENCE LTD. 2004: 605–9
View details for DOI 10.1016/j.radphyschem.2003.12.037
View details for Web of Science ID 000221290900016
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Control of Raman lasing in the nonimpulsive regime
PHYSICAL REVIEW LETTERS
2004; 92 (24)
Abstract
We explore coherent control of stimulated Raman scattering in the nonimpulsive regime. Optical pulse shaping of the coherent pump field leads to control over the stimulated Raman output. A model of the control mechanism is investigated.
View details for DOI 10.1103/PhysRevLett.92.243003
View details for Web of Science ID 000222112900010
View details for PubMedID 15245081
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Ultrafast coherent control in x-ray scattering
227th National Meeting of the American-Chemical Society
AMER CHEMICAL SOC. 2004: U270–U270
View details for Web of Science ID 000223655701408
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Ultrafast control of simple solution phase reactions
227th National Meeting of the American-Chemical Society
AMER CHEMICAL SOC. 2004: U276–U276
View details for Web of Science ID 000223655701452
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Vibrational mode coupling via an external field as a control mechanism in SRS.
227th National Meeting of the American-Chemical Society
AMER CHEMICAL SOC. 2004: U251–U251
View details for Web of Science ID 000223655701284
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Control of trapped-ion quantum states with optical pulses
PHYSICAL REVIEW LETTERS
2004; 92 (11)
Abstract
We present new results on the quantum control of systems with infinitely large Hilbert spaces. A control-theoretic analysis of the control of trapped-ion quantum states via optical pulses is performed. We demonstrate how resonant bichromatic fields can be applied in two contrasting ways--one that makes the system completely uncontrollable and the other that makes the system controllable. In some interesting cases, the Hilbert space of the qubit-harmonic oscillator can be made finite, and the Schrödinger equation controllable via bichromatic resonant pulses. Extending this analysis to the quantum states of two ions, a new scheme for producing entangled qubits is discovered.
View details for DOI 10.1103/PhysRevLett.92.113004
View details for Web of Science ID 000220344400016
View details for PubMedID 15089132
- X-ray synchrotron studies of ultrafast cyrstalline dynamics J. Synch. Rad. 2004; 12: 177-192
- Extracting quantum dynamics from feedback learning algorithms through principal component analysis DAMOP 2004
- Principal Control Analysis: Gaining Insight from Feedback Learning Algorithms Ultrafast Phenomena 2004
- Optimal field control of a ring-opening reaction DAMOP 2004
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Theory of selective excitation in stimulated Raman scattering
PHYSICAL REVIEW A
2004; 69 (1)
View details for DOI 10.1103/PhysRevA.69.013801
View details for Web of Science ID 000189304700069
- Ultrafast Coherent Control in AMO Physics DAMOP 2004
- Single shot characterization of subpicosecond and ultra-relativistic compressed electron bunches at the SLAC SPPS experiment DAMOP 2004
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Ultrafast hard x-rays from electron accelerators
4th International Conference on Ultrafast Optics
SPRINGER. 2004: 333–340
View details for Web of Science ID 000222127000043
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Half-cycle pulses in quantum information science
17th Annual Meeting of the IEEE-Lasers-and-Electro-Optics-Society
IEEE. 2004: 376–377
View details for Web of Science ID 000225390900187
- Theory of detection of angular momentum states in Rydberg atoms using half-cycle pulses DAMOP 2004
- Generation and detection of high angular momentum states in Rydberg Stark atoms DAMOP 2004
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Control of angular momentum evolution in Stark wave packets
PHYSICAL REVIEW A
2003; 68 (5)
View details for DOI 10.1103/PhysRevA.68.053405
View details for Web of Science ID 000186970900067
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Transient strain driven by a dense electron-hole plasma
PHYSICAL REVIEW LETTERS
2003; 91 (16)
Abstract
We measure transient strain in ultrafast laser-excited Ge by time-resolved x-ray anomalous transmission. The development of the coherent strain pulse is dominated by rapid ambipolar diffusion. This pulse extends considerably longer than the laser penetration depth because the plasma initially propagates faster than the acoustic modes. X-ray diffraction simulations are in agreement with the observed dynamics.
View details for DOI 10.1103/PhysRevLett.91.165502
View details for Web of Science ID 000186068300026
View details for PubMedID 14611411
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Pseudospectral methods on a semi-infinite interval with application to the hydrogen atom: a comparison of the mapped Fourier-sine method with Laguerre series and rational Chebyshev expansions
JOURNAL OF COMPUTATIONAL PHYSICS
2003; 188 (1): 56-74
View details for DOI 10.1016/S0021-9991(03)00127-X
View details for Web of Science ID 000183822700003
- Control of the Cyclohexadiene Ring-Opening Reaction Annual Meeting of the APS 2003
- AMO Physics with Coherent Control of Ultrafast Strong Field Lasers DAMOP 2003
- Ultrafast Control over Stimulated Raman Gain in Liquid Phase Annual Meeting of the APS 2003
- News and Views: Ultrafast Control Nature 421 2003; 593
- Controlling the population of angular momentum component in Rydberg states DAMOP 2003
- Coherent Excitation in Stimulated Raman Scattering Annual Meeting of the APS 2003
- Wave packet dynamics in ring-opening reactions DAMOP 2003
- Electron Spectra from Non-Sequential High Field Ionization DAMOP 2003
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Control of Rydberg atoms to perform Grover's search algorithm
32nd Winter Symposium on the Physics of Quantum Electronics
TAYLOR & FRANCIS LTD. 2002: 2339–47
View details for DOI 10.1080/0950034021000011365
View details for Web of Science ID 000180770500007
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Picosecond X-ray diffraction studies of laser-excited acoustic phonons in InSb
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
2002; 75 (4): 467-478
View details for DOI 10.1007/s003390201421
View details for Web of Science ID 000176768300002
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Quantum-state information retrieval in a Rydberg-atom data register
PHYSICAL REVIEW A
2002; 66 (2)
View details for DOI 10.1103/PhysRevA.66.022312
View details for Web of Science ID 000177872600038
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Using feedback for coherent control of quantum systems
JOURNAL OF OPTICS B-QUANTUM AND SEMICLASSICAL OPTICS
2002; 4 (3): R35-R52
View details for Web of Science ID 000176853700001
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Picosecond time-resolved x-ray diffraction probe of coherent lattice dynamics (abstract) (invited)
REVIEW OF SCIENTIFIC INSTRUMENTS
2002; 73 (3): 1361-?
View details for DOI 10.1063/1.1448147
View details for Web of Science ID 000174182800002
- Partial Field Ionization of Entangled Stark States DAMOP 2002
- Adaptive Coherent Control of Condensed Phase Molecular Reactions DAMOP 2002
- Acoustic phonon dispersion measured with time-resolved X-ray diffraction QELS 2002 proceedings 2002
- Selective Coherent Vibrational Excitation in Impulsive Stimulated Raman Scattering OSA Annual Meeting 2002
- Control of Rydberg Atoms for Performing Grover’s Search algorithm Journal of Modern Optics 2002; 49
- Time-resolved pendellosung oscillations from impulsively strained crystals QELS 2002 proceedings 2002
- Using shaped optical pulses and feedback control for selective mode-excitation in liquids OSA Annual Meeting. 2002
- Optimal control of trapped ion qubits using shaped optical pulses OSA Annual Meeting 2002
- Control of trapped ion qubits using shaped optical pulses DAMOP 2002
- Coherent Control of the Ring-Opening Reaction in Cyclohexadiene OSA Annual Meeting 2002
- Atoms, Molecules, and Light: AMO Science Enabling the Future National Research Council 2002
- Control of trapped ion qubits using shaped optical pulse DAMOP 2002
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Above-threshold double-ionization spectroscopy of argon
PHYSICAL REVIEW A
2001; 64 (5)
View details for Web of Science ID 000172074200066
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Coherent control of pulsed X-ray beams
NATURE
2001; 413 (6858): 825-828
Abstract
Synchrotrons produce continuous trains of closely spaced X-ray pulses. Application of such sources to the study of atomic-scale motion requires efficient modulation of these beams on timescales ranging from nanoseconds to femtoseconds. However, ultrafast X-ray modulators are not generally available. Here we report efficient subnanosecond coherent switching of synchrotron beams by using acoustic pulses in a crystal to modulate the anomalous low-loss transmission of X-ray pulses. The acoustic excitation transfers energy between two X-ray beams in a time shorter than the synchrotron pulse width of about 100 ps. Gigahertz modulation of the diffracted X-rays is also observed. We report different geometric arrangements, such as a switch based on the collision of two counter-propagating acoustic pulses: this doubles the X-ray modulation frequency, and also provides a means of observing a localized transient strain inside an opaque material. We expect that these techniques could be scaled to produce subpicosecond pulses, through laser-generated coherent optical phonon modulation of X-ray diffraction in crystals. Such ultrafast capabilities have been demonstrated thus far only in laser-generated X-ray sources, or through the use of X-ray streak cameras.
View details for Web of Science ID 000171750200040
View details for PubMedID 11677601
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Particles driven to diffraction
NATURE
2001; 413 (6852): 117-118
View details for Web of Science ID 000170918800028
View details for PubMedID 11557960
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Optimally shaped terahertz pulses for phase retrieval in a Rydberg-atom data register
PHYSICAL REVIEW A
2001; 64 (3)
View details for Web of Science ID 000170978600085
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Dynamics and coherent control of high-amplitude optical phonons in bismuth
PHYSICAL REVIEW B
2001; 64 (9)
View details for Web of Science ID 000170726000005
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Coherent learning control of vibrational motion in room temperature molecular gases
CHEMICAL PHYSICS LETTERS
2001; 344 (3-4): 333-338
View details for Web of Science ID 000170676000014
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Coherent control using adaptive learning algorithms
PHYSICAL REVIEW A
2001; 63 (6)
View details for Web of Science ID 000169134800071
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Probing impulsive strain propagation with x-ray pulses
PHYSICAL REVIEW LETTERS
2001; 86 (14): 3072-3075
Abstract
Pump-probe time-resolved x-ray diffraction of allowed and nearly forbidden reflections in InSb is used to follow the propagation of a coherent acoustic pulse generated by ultrafast laser excitation. The surface and bulk components of the strain could be simultaneously measured due to the large x-ray penetration depth. Comparison of the experimental data with dynamical diffraction simulations suggests that the conventional model for impulsively generated strain underestimates the partitioning of energy into coherent modes.
View details for Web of Science ID 000167866300040
View details for PubMedID 11290110
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Quantum phase retrieval of a Rydberg wave packet using a half-cycle pulse
PHYSICAL REVIEW LETTERS
2001; 86 (7): 1179-1182
Abstract
A terahertz half-cycle pulse was used to retrieve information stored as quantum phase in an N-state Rydberg atom data register. The register was prepared as a wave packet with one state phase reversed from the others (the "marked bit"). A half-cycle pulse then drove a significant portion of the electron probability into the flipped state via multimode interference.
View details for Web of Science ID 000166907600009
View details for PubMedID 11178038
- "Controlling a Rydberg wave packet using a half-cycle pulse DAMOP 2001
- Coherent Control and Dynamics of High Amplitude Optical Phonons in Bi Phys. Rev. B 2001; 84
- Optimally shaped terahertz pulses for a quantum algorithm on a Rydberg atom data register Physical Review A 2001; 64
- Study of Coherent Raman Energy Transfer in Molecular Liquids with Strong Field Laser Excitation DAMOP 2001
- Above-Threshold Double Ionization Spectroscopy of Argon 2001: 053405
- Time-Resolved Anomalous Transmission of X-ray in laser heated Germainium QTuF6 2001
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Femtosecond X-ray diffraction: Experiments and limits
Conference on X-Ray FEL Optics and Instrumentation
SPIE-INT SOCIETY OPTICAL ENGINEERING. 2001: 26–37
View details for Web of Science ID 000168537600005
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Ultrafast quantum control in atoms and molecules
XVIIth International Conference on Atomic Physics
AMER INST PHYSICS. 2001: 463–477
View details for Web of Science ID 000167777800034
- Time-resolved x-ray Pendellösung oscillations in impulsively strained crystals DAMOP 2001
- Programmable Terahertz waveform generation DAMOP 2001
- Shaped Terahertz Pulses for a Quantum Algorithm in a Rydberg Atom DAMOP 2001
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Does Rydberg state manipulation equal quantum computation?
Science
2000; 289 (5484): 1431a-?
View details for PubMedID 17839509
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Information storage and retrieval through quantum phase
SCIENCE
2000; 287 (5452): 463-465
View details for Web of Science ID 000084929900040
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Time-resolved X-ray diffraction from coherent phonons during a laser-induced phase transition
PHYSICAL REVIEW LETTERS
2000; 84 (1): 111-114
View details for Web of Science ID 000084587900028
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Toward strong field mode-selective chemistry
8th International Conference on Multiphoton Processes (ICOMP VIII)
AMER INST PHYSICS. 2000: 613–619
View details for Web of Science ID 000089140300058
- Learning to Control Dissociative Ionization in a Diatomic Molecule DAMOP 2000
- Picosecond Synchrotron X-ray Diffraction Study of Lattice Dynamics of Laser-irradiated InSb Physical Review Letters. 2000; 84: 111-4
- Quantum information storage and retrieval in Rydberg wave packets Science 2000; 287
- Algorithms for Strong Field Quantum Wave Packet Control DAMOP 2000
- Progress Toward a Test of Parity-Conserving Time-Reversal Invariance DAMOP 2000
- Learning how to control vibrations in multimode molecules QThM4 2000
- ATI Spectra from Non-Sequential Double Ionization of Argon DAMOP 2000
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THz emission from coherently controlled photocurrents in GaAs
APPLIED PHYSICS LETTERS
1999; 75 (25): 3959-3961
View details for Web of Science ID 000084242700019
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Toward strong field mode-selective chemistry
JOURNAL OF PHYSICAL CHEMISTRY A
1999; 103 (49): 10166-10168
View details for Web of Science ID 000084318700016
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A trimodal resonator for three mutually perpendicular magnetic fields
REVIEW OF SCIENTIFIC INSTRUMENTS
1999; 70 (3): 1780-1786
View details for Web of Science ID 000079012100033
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Controlling the shape of a quantum wavefunction
NATURE
1999; 397 (6716): 233-235
View details for Web of Science ID 000078184800045
- Strong Field Control of Multiphoton Ionization in the Time and Frequency Domain Abstract of Ottawa workshop on strong fields 1999
- THz emission from coherently controlled currents in GaAs CLEO/QELS Joint Abstract JThC5 1999
- Impulsive coherent control of x-rays in Bragg crystals Invited abstract in Applications of High Field and Short Wavelength Sources VIII 1999
- Ultrafast structural dynamics in InSb measured using time-resolved x-ray diffraction QELS contributed abstract QThJ4 1999
- Wave Packet Sculpting and Quantum Algorithms Invited Abstract for CAP Congress 1999
- Wave packets and Half-cycle Pulses Wavepackets edited by Yaezell, J. New York: John Wiley. 1999
- Feedback Control of Molecular Liquids Invited Abstract for Ottawa workshop on strong fields 1999
- The Phonon Bragg Switch: A Proposal to Generate Sub-Picosecond X-Ray Pulses Abstract of contributed talk at the Annual Meeting 1999
- Quantum Control and Quantum Algorithms Invited Abstract for LPHYS'99 1999
- Ultrafast structural dynamics in indium antimonide probed by time-resolved x-ray diffraction Proceedings of ILS-XV 1999: 133
- Fast quantum search using coherent electronic states of Rydberg atoms QELS Contributed Abstract QMA5 1999
- Population dynamics of a triply driven, three-level atomic system Abstract of poster at the Annual Meeting 1999
- Control and measurement of quantum wave packets QELS Invited Abstract 1999
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Measurement of the amplitude and phase of a sculpted Rydberg wave packet
PHYSICAL REVIEW LETTERS
1998; 80 (25): 5508-5511
View details for Web of Science ID 000074313000012
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Ultrafast structural changes measured by time-resolved X-ray diffraction
APPLIED PHYSICS A-MATERIALS SCIENCE & PROCESSING
1998; 66 (6): 587-591
View details for Web of Science ID 000073953200001
- Programmable structure in Rydberg systems Bull. Am. Phys. Soc. 1998
- Complete Measurement and Control of Rydberg Wave Packets Springer Series in Chemical Physics edited by Elsässer, T., Fujimoto, J. G., Wiersma, D., Zinth, W. 1998
- Creating and Observing Stroboscopic Molecular Wave Packets IQEC'98 abstract. 1998
- Resonant Effects in Above Threshold Ionization Springer Series in Chemical Physics edited by Elsässer, T., Fujimoto, J. G., Wiersma, D., Zinth, W. 1998
- Adaptive Control of Quantum Phase in Rydberg Wavepackets IQEC'98 abstract. 1998
- Strong-Field THz Interactions with Wavepackets Bull Am. Phys. Soc. 1998
- Quantum wavepacket sculpting with shaped ultrafast radiation Abstract of Plenary Talk at ILS'98 1998
- New resonant effects in ATI spectra: rescattering and electron-electron correlation Proceedings of LPHYS'98 1998
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Resonant double-excitation induced by wiggling ATI electrons
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
1997; 30 (23): L843-L850
View details for Web of Science ID 000071070000003
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Redistribution of atomic Rydberg states by tunable narrow band picosecond far-infrared pulses
OPTICS EXPRESS
1997; 1 (7): 186-196
Abstract
We study the redistribution of Cesium atomic Rydberg states by intense, shaped, narrow-band pulses of millimeter radiation. The radiation source is a large-area photoconductive switch illuminated by a temporally shaped optical pulse. We will present our latest efforts to study atomic redistribution in the strong-field limit using these table-top THz sources.
View details for Web of Science ID 000208802100003
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Ultrafast x-ray diffraction using a streak-camera detector in averaging mode
OPTICS LETTERS
1997; 22 (13): 1012-1014
Abstract
We demonstrate an apparatus for measuring time-dependent x-ray diffraction. X-ray pulses from a synchrotron are diffracted by a pair of Si(111) crystals and detected with an x-ray streak camera that has single-shot resolution of better than 1 ps. The streak camera is driven by a photoconductive switch, which is triggered by 100-fs laser pulses at a repetition rate of 1 kHz. The laser and the streak camera are synchronized with the synchrotron pulses. In the averaging mode, trigger jitter results in 2-ps temporal resolution. We measured the duration of 5-keV pulses from the Advanced Light Source synchrotron to be 70ps.
View details for Web of Science ID A1997XG25300024
View details for PubMedID 18185736
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Propagation of half-cycle far infrared pulses
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
1997; 14 (7): 1651-1655
View details for Web of Science ID A1997XL99900015
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Core scattering of Stark wave packets
PHYSICAL REVIEW A
1997; 56 (1): 636-639
View details for Web of Science ID A1997XL64500076
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Stark wave packets viewed with half-cycle pulses
PHYSICAL REVIEW A
1997; 55 (6): R3995-R3998
View details for Web of Science ID A1997XE37200005
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Melting of a semiconductor crystal (InSb) with a short laser pulse (100 fs)
4th High Heat Flux Engineering Conference, as part of the SPIE International Symposium on Optical Science, Engineering, and Instrumentation
SPIE - INT SOC OPTICAL ENGINEERING. 1997: 102–106
View details for Web of Science ID 000071550400009
- Core-Scattering of Stark Wavepackets Physical Review A (Atomic, Molecular, and Optical Physics) 1997; 56
- Stark Wavepackets Viewed with Half-Cycle Pulses Physical Review A (Atomic, Molecular, and Optical Physics) 1997; 55: R3995-8
- Evidence for Resonant Effects in High-Order ATI Spectra QELS '97 Program Abstracts 1997
- High order resonances in Above Threshold Ionization APS Bulletin for Southeast Section Meeting 1997
- Ramsey Interference of 'Stroboscopic' Rydberg States of Diatomic Molecules Bull Am. Phys. Soc. 1997
- Propagation of half-cycle far infrared pulse Journal of the Optical Society of America B (Optical Physics) 1997; 14: 1651-5
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Evidence for resonant effects in high-order ATI spectra
7th International Conference on Multiphoton Processes
IOP PUBLISHING LTD. 1997: 67–77
View details for Web of Science ID A1997BH40C00008
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Phase dependence of intense-field ionization
PHYSICAL REVIEW A
1996; 54 (5): 4271-4278
View details for Web of Science ID A1996VT67300071
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Ionization of Rydberg wave packets by subpicosecond, half-cycle electromagnetic pulses
PHYSICAL REVIEW LETTERS
1996; 76 (14): 2436-2439
View details for Web of Science ID A1996UC77700008
- Controlling Core Scattering in Stark Rydberg Wavepackets Bull Am. Phys. Soc. 1996
- Evidence for Resonant Effects in High-Order ATI Spectra Proceedings of the International Conference on Multiphoton Processes (ICOMP) 1996
- Ionization of Rydberg Wavepackets by Sub-Picosecond, Half-Cycle Electromagnetic Pulses Physical Review Letters 1996; 76 (2436)
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Measurement of the polarization state of high harmonics generated in gases
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
1996; 13 (1): 157-161
View details for Web of Science ID A1996TP06000021
- Two-Photon doppler-Free Spectroscopy at High Magnetic Field Bull. of the Am. Phys. Soc. 1996: 1112
- Coherent Control of Above-Threshold Ionization Super-Intense Laser-Atom Physics IV edited by Muller, H. G., Federov, M. 1996
- Progress towards Simultaneous Tri-Color Resonance for a Three State Atomic Clock Bull Am. Phys. Soc. 1996
- Observation of Atomic Wavepacket Evolution in a Non-Separable System Laser Spectroscopy: XII International Conference edited by Inguscio, M., Allegrini, M., Sasso, A. 1996: 299
- Optical Pumping at High Magnetic Field Using an External Cavity Diode Laser Bull Am. Phys. Soc. 1996
- Sculpting Terahertz Bull Am. Phys. Soc. 1996
- Evolution of Entangled Wave Packets in Diatomic Molecules Bull Am. Phys. Soc. 1996
- High Powered Half-Cycle Thz Pulses IEEE Conference Record - Abstracts. 1996 IEEE International Conference on Plasma Science 1996
- Terahertz Ionization of Stark Switched Rydberg States ILS meeting 1996
- Rydberg Wavepackets and Half-Cycle THz Pulses The 15th International Conference on Atomic Physics (ZICAP) 1996
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PROGRAMMABLE CESIUM RYDBERG WAVE-PACKETS
PHYSICAL REVIEW A
1995; 52 (6): 4719-4726
View details for Web of Science ID A1995TK65200053
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BOUND-STATE INTERFEROMETRY USING INCOHERENT-LIGHT
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
1995; 28 (13): L405-L411
View details for Web of Science ID A1995RK87700001
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NEW LIGHT ON AN OLD PROBLEM
PHYSICS WORLD
1995; 8 (6): 27-27
View details for Web of Science ID A1995RD17900028
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POLARIZATION OF HIGH-INTENSITY HIGH-HARMONIC GENERATION
PHYSICAL REVIEW A
1995; 51 (5): R3433-R3436
View details for Web of Science ID A1995RA43100010
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IONIZATION OF ORIENTED RYDBERG STATES BY SUBPICOSECOND HALF-CYCLE ELECTROMAGNETIC PULSES
PHYSICAL REVIEW A
1995; 51 (4): R2687-R2690
View details for Web of Science ID A1995QT40100008
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RINGS IN ABOVE-THRESHOLD IONIZATION - A QUASI-CLASSICAL ANALYSIS
PHYSICAL REVIEW A
1995; 51 (2): 1495-1507
View details for Web of Science ID A1995QH07100081
- Observation of Atomic Wavepacket Dynamics in a Non-Separable Hamiltonian System 1995
- Observation of Pulse Shape Dependence of Multiphoton Ionization Rates in Xenon and Krypton Bulletin of the American Physical Society 1995: 1274
- Rydberg Atoms Irradiated by Ultra-short Terahertz Pulses Comments on Atomic and Molecular Physics 1995; 30: 347
- Direct Observation of Radial Wavepacket Dynamics using Half-Cycle Sub-Picosecond Pulses 1995
- Scaled-time dynamics of ionization of Rydberg Stark stated by half-cycle pulses Journal of Physics B: Atomic, Molecular, And Optical Physics 1995; 28: L457
- Measurement of the Polarization of High Harmonic Radiation Bulletin of the American Physical Society 1995: 1274
- Measuring Parity Conserving Time Reversal Violating Interactions in Atomic Systems Bulletin of the American Physical Society 1995: 1280
- Beyond ATI: Strong Field Quantum Control American Institute of Physics Press edited by Wineland, D. J., Wieman, C. E., Smith, S. J. 1995: 416–33
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PHASE DEPENDENCE OF INTENSE FIELD-IONIZATION - A STUDY USING 2 COLORS
PHYSICAL REVIEW LETTERS
1994; 73 (10): 1344-1347
View details for Web of Science ID A1994PE72700009
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COHERENT GENERATION OF FAR-INFRARED RADIATION FROM INP
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
1994; 11 (3): 486-491
View details for Web of Science ID A1994NB82200011
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INTERACTIONS OF ATOMS WITH HIGH-FIELD SINGLE-CYCLE INFRARED RADIATION
11th International Conference on Laser Spectroscopy
AIP PRESS. 1994: 227–30
View details for Web of Science ID A1994BA06J00048
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FEMTOSECOND RAMSEY FRINGES IN STRONGLY-DRIVEN RYDBERG SYSTEMS
11th International Conference on Laser Spectroscopy
AIP PRESS. 1994: 319–24
View details for Web of Science ID A1994BA06J00068
- Coherent Generation of FIR Radiation from InP Journal of the Optical Society of Americal B 1994; 11: 486
- Phase Dependence of Intense-Field Ionization: A Study Using Two Colors Physical Review Letters 1994; 73: 1344
- High average power chirped pulse amplification systems Proceedings of CLEO/IQEC 1994
- Production of Programmable Amplified, Shaped Pulses in Femtosecond Lasers Springer Series in Chemical Physics edited by Barbara, P. F., Knox, W. H., Mourou, G. A., Zewail, A. H. 1994: 180
- Study and Control of Ionization and Dissociation Dynamics Using Two-Colors 1994: 1087
- Rotation of Elliptical Polarization in High Harmonic Generation Proceedings of the OSA Topical Conference on High Field Interactions and Short Wavelength Generation edited by Milchberg, H., Freeman, R. R. 1994
- Programmable Wavefunction Engineering in Cs Rydberg States Springer Series in Chemical Physics edited by Barbara, P. F., Knox, W. H., Mourou, G. A. 1994: 240
- Elliptical Polarization in High Harmonic Generation 1994: 1087
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RAMSEY INTERFERENCE IN STRONGLY DRIVEN RYDBERG SYSTEMS
PHYSICAL REVIEW LETTERS
1993; 71 (16): 2575-2578
View details for Web of Science ID A1993MC11900016
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IONIZATION OF RYDBERG ATOMS BY SUBPICOSECOND HALF-CYCLE ELECTROMAGNETIC PULSES
PHYSICAL REVIEW LETTERS
1993; 70 (9): 1236-1239
View details for Web of Science ID A1993KN88700013
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LIGHT-INDUCED VIBRATIONAL STRUCTURE IN H-2+ AND D2+ IN INTENSE LASER FIELDS
PHYSICAL REVIEW LETTERS
1993; 70 (8): 1077-1080
View details for Web of Science ID A1993KM77900012
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GENERATION OF HIGH-POWER SUB-SINGLE-CYCLE 500-FS ELECTROMAGNETIC PULSES
OPTICS LETTERS
1993; 18 (4): 290-292
View details for Web of Science ID A1993KK80800012
View details for PubMedID 19802113
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GENERATION AND APPLICATION OF HIGH-POWER, 500 FS ELECTROMAGNETIC PULSES
5TH TOPICAL MEETING ON ULTRAFAST ELECTRONICS AND OPTOELECTRONICS
OPTICAL SOC AMERICA. 1993: 108–111
View details for Web of Science ID A1993BZ18T00025
- Light-Induced structure in atoms and molecules 1993: 1751
- Manifestation of Fourth Order Nonlinear Effect in FIR Generation from InP 1993: 1720
- Femtosecond Ramsey Fringes in Strongly Driven Rydberg System Proceedings of the 11th Conference on Laser, Spectroscopy 1993
- Light-Induced Bound Vibrational States of H2 and D2 in Intense Laser Fields Physical Review Letters 1993; 70: 1077
- High Intensity Above-Threshold Ionization of He Short Wavelength Coherent Radiation: Generation and Applications edited by Perry, M. D. 1993
- Physics of Single-Cycle Far-Infrared Interactions with Atoms 1993: 200
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ELECTRON-ENERGY RESOLVED EXPERIMENTS ON MULTIPHOTON DETACHMENT FROM NEGATIVE-IONS
NATO Advanced Research Workshop on SILAP (Super-Intense Laser-Atom Physics)
PLENUM PRESS DIV PLENUM PUBLISHING CORP. 1993: 483–491
View details for Web of Science ID A1993BZ91G00040
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HIGH-INTENSITY ABOVE-THRESHOLD IONIZATION OF HE AND HE ION
5th Topical Meeting on the Generation of Shortwavelength Radiation: Physics with Intense Laser Pulses
OPTICAL SOC AMERICA. 1993: 72–74
View details for Web of Science ID A1993BA05X00016
- Interactions of Atoms with High-Field Single-Cycle Infrared Radiation Proceedings of the 11th Conference on Laser, Spectroscopy 1993
- H2 in Intense Laser Fields Molecules in Laser fields edited by Brandrauk, A., Press, D. 1993
- Strong Field Coherent Control Proceedings of the Fifth International Conference on Multiphoton Physics 1993
- Atomic Physics with Intense, Subpicosecond Half-Cycle Pulses 1993: 1137
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ATOMIC PHYSICS WITH INTENSE, SUBPICOSECOND HALF-CYCLE PULSES
NATO Advanced Research Workshop on SILAP (Super-Intense Laser-Atom Physics)
PLENUM PRESS DIV PLENUM PUBLISHING CORP. 1993: 287–299
View details for Web of Science ID A1993BZ91G00025
- Phase-Dependent Ionization Using an Intense Two-Color Light Field with Calibrated Phase Difference 1993
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POPULATION TRAPPING IN KR AND XE IN INTENSE LASER FIELDS
PHYSICAL REVIEW A
1993; 47 (1): R49-R52
View details for Web of Science ID A1993KG72500014
- Generation of High-Power Half-Cycle 500 Femtosecond Electromagnetic Pulses Optics Letters 1993; 18: 290
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LONGER WAVELENGTHS REQUIRE LOWER INTENSITY IN MULTIPHOTON DETACHMENT OF NEGATIVE-IONS
PHYSICAL REVIEW LETTERS
1992; 69 (24): 3459-3462
View details for Web of Science ID A1992KB85700011
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INTERACTION OF FREE-ELECTRONS WITH AN INTENSE FOCUSED LASER-PULSE IN GAUSSIAN AND CONICAL AXICON GEOMETRIES
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
1992; 9 (12): 2190-2195
View details for Web of Science ID A1992KD64700007
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ABOVE-THRESHOLD PHOTODISSOCIATION AND BOND SOFTENING AT HIGH INTENSITIES
NATO ADVANCED RESEARCH WORKSHOP ON COHERENCE PHENOMENA IN ATOMS AND MOLECULES IN LASER FIELDS
PLENUM PRESS DIV PLENUM PUBLISHING CORP. 1992: 53–63
View details for Web of Science ID A1992BV70Z00006
- Generation of High Power THz Radiation 1992: 1140
- Generation of High-Power Single-Cycle Picosecond Radiation Springer Verlag Series in Chemical PHysics edited by Martin, J. -., Migus, A., Mourou, G. A., Zewail, A. H. 1992: 490
- Phase Dependent Ionization Using An Intense Two-Color Light Field 1992: 1141
- Population Trapping in Atoms Exposed to Intense Laser Fields 1992: 1131
- Stability of Atoms in Intense Laser Fields Atomic Physics edited by Walther, H. 1992: 485–98
- Stability of Stark States in Intense Laser Fields 1992: 1079
- Short Wavelength Coherent Radiation: Generation and Applications, 1992
- Phase-Dependent Ionization Using an Intense Two-Color Light Field Springer Verlag Series in Chemical PHysics edited by Martin, J. L., Migus, A., Mourou, G. A. 1992
- Light-Induced Molecular Bound States in Intense Laser Fields 1992: 1140
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IONIZATION SUPPRESSION OF STARK STATES IN INTENSE LASER FIELDS
PHYSICAL REVIEW LETTERS
1991; 67 (23): 3215-3218
View details for Web of Science ID A1991GT01400004
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INTERFEROMETRIC CHARACTERIZATION OF 160 FS FAR-INFRARED LIGHT-PULSES
APPLIED PHYSICS LETTERS
1991; 59 (8): 893-895
View details for Web of Science ID A1991GB29600004
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HIGH-RESOLUTION MULTIPHOTON IONIZATION AND DISSOCIATION OF H2 AND D2 MOLECULES IN INTENSE LASER FIELDS
PHYSICAL REVIEW A
1991; 44 (3): R1458-R1461
View details for Web of Science ID A1991GA16900009
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INVESTIGATIONS OF ABOVE-THRESHOLD IONIZATION USING SUBPICOSECOND LASER-PULSES
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
1991; 24 (2): 325-347
View details for Web of Science ID A1991EV89600004
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IONIZATION AND DISSOCIATION OF MOLECULAR-HYDROGEN BY ULTRASHORT LIGHT-PULSES
5TH TOPICAL MEETING ON SHORT-WAVELENGTH COHERENT RADIATION : GENERATION AND APPLICATIONS / SPECIAL TOPICAL MEETING ON SOFT-X-RAY PROJECTION LITHOGRAPHY
OPTICAL SOC AMERICA. 1991: 222–226
View details for Web of Science ID A1991BW05V00047
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SOFTENING OF THE MOLECULAR-BOND IN INTENSE LASER FIELDS
12TH INTERNATIONAL CONF ON ATOMIC PHYSICS ( ICAP-12 )
AIP PRESS. 1991: 325–335
View details for Web of Science ID A1991BU34P00022
- New Tests of P-Conserving T-Violation in Atoms 1991: 1267
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NONLINEAR COMPTON-SCATTERING IN A PULSED FOCUSED LASER-BEAM
5TH TOPICAL MEETING ON SHORT-WAVELENGTH COHERENT RADIATION : GENERATION AND APPLICATIONS / SPECIAL TOPICAL MEETING ON SOFT-X-RAY PROJECTION LITHOGRAPHY
OPTICAL SOC AMERICA. 1991: 252–256
View details for Web of Science ID A1991BW05V00054
- Photoionization of Atoms with Ultrashort Laser Pulses Advances in Atomic, Molecular, and Optical Physics, Supplement 1 edited by Gavrila, M. 1991
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IONIZATION AND DISSOCIATION OF H2 IN INTENSE LASER FIELDS AT 1.064-MU-M, 532 NM, AND 355-NM
PHYSICAL REVIEW A
1990; 42 (9): 5500-5513
View details for Web of Science ID A1990EH11900060
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ABOVE-THRESHOLD IONIZATION WITH A 2-COLOR LASER FIELD
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
1990; 23 (16): 2761-2769
View details for Web of Science ID A1990DW24300018
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SOFTENING OF THE H2+ MOLECULAR-BOND IN INTENSE LASER FIELDS
PHYSICAL REVIEW LETTERS
1990; 64 (16): 1883-1886
View details for Web of Science ID A1990CZ05900009
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NONRESONANT ABOVE-THRESHOLD IONIZATION BY CIRCULARLY POLARIZED SUBPICOSECOND PULSES
PHYSICAL REVIEW A
1990; 41 (7): 4119-4121
View details for Web of Science ID A1990CY12500095
- Introduction to the High Intensity Physics of Atoms and Free Electrons Atoms in Strong Fields,, NATO Advanced Study Institute edited by Nicolaides, C. A., Clark, C. W., Nayfeh, M. H. 1990
- Ionization and Dissociation of H2 in Intense Laser Fields at 1064 nm, 532 nm, and 355 nm Physical Review A 1990; 42: 5500
- Above-threshold ionization with a 2-color radiation field Journal of Physics B. 1990; 23: 2761
- Bond Softening and Above Threshold Dissociation in H2 Multiphoton Processes edited by Mainfay, G., Agostini, P. 1990: 181
- Above-Threshold Ionization with a 2-Color Laser Field 1990: 1151
- Softening of the H2+ Molecular Bond in Intense Laser Fields 1990: 1152
- Photoionization and Dissociation of Molecular Hydrogen in Intense Laser Fields Bulletin of the American Physical Society 1989: 1385
- Recent Progress in Above-Threshold Ionization Proceedings of ICPEAC XVI 1989
- Polarization Effects in ATI Academic Press edited by Feld, M. S., Thomas, J. E., Mooradian, A. 1989
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SOLID-PHASE EPITAXY OF LASER AMORPHIZED SILICON
APPLIED PHYSICS LETTERS
1988; 53 (15): 1402-1404
View details for Web of Science ID A1988Q417600016
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HIGH-INTENSITY KAPITZA-DIRAC EFFECT
PHYSICAL REVIEW LETTERS
1988; 61 (10): 1182-1185
View details for Web of Science ID A1988P902600011
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THE PONDEROMOTIVE POTENTIAL OF HIGH-INTENSITY LIGHT AND ITS ROLE IN THE MULTIPHOTON IONIZATION OF ATOMS
IEEE JOURNAL OF QUANTUM ELECTRONICS
1988; 24 (7): 1461-1469
View details for Web of Science ID A1988P509500029
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ASYMMETRIES IN ABOVE-THRESHOLD IONIZATION
PHYSICAL REVIEW LETTERS
1988; 60 (24): 2458-2461
View details for Web of Science ID A1988N799600004
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ABOVE-THRESHOLD IONIZATION IN HELIUM
PHYSICAL REVIEW A
1988; 37 (9): 3615-3618
View details for Web of Science ID A1988N252300062
- Above-Threshold Ionization and Electron Scattering in Intense Light Proceedings of the Eleventh International Conference on Atomic Physics held in Paris 1988
- Above-Threshold Ionization and the Quantum Mechanics of Wiggling Electrons Atomic and Molecular Processes with Short Intense Laser Pulses edited by Bandrauk, A. D. 1988
- Atoms in Intense Optical Fields: Ponderomotive Forces and Above-Threshold Ionization edited by Taylor, K. T., Nayfeh, M. H. 1988
- Symmetries and Asymmetries in Above-Threshold Ionization Optical Society Proceedings on Short Wavelength Coherent Radiation: Generation and Applications edited by Falcone, R. W., Kirz, J. 1988
- Investigations of the Role of Ponderomotive Forces in ATI Using Subpicosecond Laser Pulses Multiphoton Processes edited by Smith, S. 1988
- Atomic Photoionization in Intense Optical Fields Proc. of SPIE 1988: 17
- Stimulated Compton Backscattering and the High Intensity Kapitza-Dirac Effect Optical Society Proceedings on Short Wavelength Coherent Radiation: Generation and Applications edited by Falcone, R. W., Kirz, J. 1988: 236
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ABOVE-THRESHOLD IONIZATION WITH SUBPICOSECOND LASER-PULSES
PHYSICAL REVIEW LETTERS
1987; 59 (10): 1092-1095
View details for Web of Science ID A1987J891800008
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ABOVE-THRESHOLD IONIZATION WITH ELLIPTICALLY POLARIZED-LIGHT
PHYSICAL REVIEW LETTERS
1987; 59 (3): 274-277
View details for Web of Science ID A1987J252200007
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ABOVE-THRESHOLD IONIZATION PROCESSES IN XENON AND KRYPTON
PHYSICAL REVIEW A
1987; 35 (11): 4611-4623
View details for Web of Science ID A1987H506900020
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ROLE OF THE PONDEROMOTIVE POTENTIAL IN ABOVE-THRESHOLD IONIZATION
JOURNAL OF THE OPTICAL SOCIETY OF AMERICA B-OPTICAL PHYSICS
1987; 4 (5): 760-764
View details for Web of Science ID A1987K232100020
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SCATTERING OF ELECTRONS BY INTENSE COHERENT-LIGHT
PHYSICAL REVIEW LETTERS
1987; 58 (4): 349-352
View details for Web of Science ID A1987F688800017
- A Study of Above Threshold Ionization Processes in Xenon and Krypton Physical Review Letters A 1987; 35: 4611
- Scattering of Free Electrons by Light Physics News of 1986, in Physics Today 1987; 40: S-48
- An Equation for Melting and Freezing Transition Rates Beam-Solid Interactions and Transient Processes 1987
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PONDEROMOTIVE EFFECTS ON ANGULAR-DISTRIBUTIONS OF PHOTOELECTRONS
PHYSICAL REVIEW LETTERS
1986; 57 (25): 3156-3159
View details for Web of Science ID A1986F276600009
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PICOSECOND SURFACE ELECTRON DYNAMICS ON PHOTOEXCITED SI(111) (2X1) SURFACES
PHYSICAL REVIEW LETTERS
1986; 57 (7): 881-884
View details for Web of Science ID A1986D611100026
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SUPPRESSION OF MULTIPHOTON IONIZATION WITH CIRCULARLY POLARIZED COHERENT-LIGHT
PHYSICAL REVIEW LETTERS
1986; 56 (24): 2590-2593
View details for Web of Science ID A1986C746800011
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TIME AND ANGLE RESOLVED ULTRAVIOLET PHOTOEMISSION SPECTROSCOPY STUDIES OF SINGLE-CRYSTAL SURFACE AND INTERFACES
JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A
1986; 4 (3): 1481-1486
View details for Web of Science ID A1986C819300117
- Picosecond Time-Resolved Photoemission Spectroscopy of Semiconductor Surfaces Proc. of the Seventh International Conference on Laser Spectroscopy 1986
- Studies of Intensity and Polarization Effects on ATI Electrons from Xe Multiphoton Ionization Proceedings of the Workshop on High Intensity Multiphoton Ionization 1986
- Electron Angular Distributions in Above Threshold Ionization of Xenon Proceedings of the Third Topical Meeting on Short Wavelength Coherent Radiation: Generation and Applications edited by Bokor, J., Attwood, D. T. 1986
- Intensity and Polarization Effects on Above Threshold Ionization Bulletin of the American Physical Society 1986: 947
- Suppression of Multiphoton Ionization with Circularly Polarized Coherent Light Proceedings of the Third Topical Meeting on Short Wavelength Coherent Radiation: Generation and Applications edited by Bokor, J., Attwood, D. T. 1986
- Time-resolved VUV Photoemission Spectroscopy Proceedings of the Third Topical Meeting on Short Wavelength Coherent Radiation: Generation and Applications edited by Bokor, J., Attwood, D. T. 1986
- Ultraviolet photoemission studies of surfaces using picosecond pulses of coherent XUV radiation Springer series in chemical physics edited by Fleming, G. R., Seigman, A. E. 1986
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PICOSECOND TIME-RESOLVED PHOTOEMISSION-STUDY OF THE INP(110) SURFACE
PHYSICAL REVIEW LETTERS
1985; 54 (12): 1302-1305
View details for Web of Science ID A1985ADW6700025
- Time and angle resolved photoemission study of InP(110) Physical Review B 1985; 32: 3669
- Relation between temperature and solidification velocity in rapidly cooled liquid silicon 1985
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TIME-RESOLVED AND ANGLE-RESOLVED PHOTOEMISSION-STUDY OF INP(110)
PHYSICAL REVIEW B
1985; 32 (6): 3669-3675
View details for Web of Science ID A1985AQN2000042
- Generation of 35 nm coherent radiation Proceedings of the SPIE 1984: 42
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PHOTOEMISSION-STUDIES OF SURFACES USING PICOSECOND PULSES OF COHERENT EXTREME-ULTRAVIOLET RADIATION
OPTICAL SOC AMER. 1984: 529–29
View details for Web of Science ID A1984SU90700204
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PHOTOEMISSION APPARATUS USING XUV HARMONICS OF A PICOSECOND KRF LASER
PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS
1984; 476: 61-64
View details for Web of Science ID A1984TJ18700010
- Measurement of ultrafast melting and regrowth velocities in pulsed laser heated silicon Energy Beam-Solid Interactions and Transient Thermal Processing edited by Fan, J. C., Johnson, N. M. 1984: 93
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GENERATION OF 35-NM COHERENT RADIATION
PROCEEDINGS OF THE SOCIETY OF PHOTO-OPTICAL INSTRUMENTATION ENGINEERS
1984; 461: 42-44
View details for Web of Science ID A1984SS86400008
- Absorption induced by electronic transitions Nuclear Instruments and Methods 1984; B2: 457
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RAPID MELTING AND REGROWTH VELOCITIES IN SILICON HEATED BY ULTRAVIOLET PICOSECOND LASER-PULSES
PHYSICAL REVIEW LETTERS
1984; 53 (2): 182-185
View details for Web of Science ID A1984SY87200021
- Weak Interactions of Leptons and Quarks New York: Cambridge University Press. 1983
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TIME RESOLVED AMORPHOUS-SILICON FORMATION FROM LASER MELTED LIQUID SILICON FILMS
AIP CONFERENCE PROCEEDINGS
1983: 279-287
View details for Web of Science ID A1983QZ37800036
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GENERATION OF 35.5-NM COHERENT RADIATION
OPTICS LETTERS
1983; 8 (4): 217-219
Abstract
Tunable coherent radiation was produced at 35.5 nm by seventh-harmonic conversion of 248-nm radiation from a krypton fluoride excimer laser. The nonlinear interaction took place at the intersection of the laser focus and a pulsed, supersonic helium gas jet. Third- and fifth-harmonic generation produced coherent outputs at 83 and 50 nm in both helium and xenon gas jets.
View details for Web of Science ID A1983QH18500007
View details for PubMedID 19714189
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MEASUREMENT OF PICOSECOND ULTRAVIOLET-LASER PULSE-WIDTHS USING AN ELECTRICAL AUTO-CORRELATOR
APPLIED PHYSICS LETTERS
1983; 42 (4): 342-344
View details for Web of Science ID A1983QB27600013
- Generation of 35 nm coherent radiation Optics Letters 1983; 8: 217
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WAVELENGTH CONVERSION WITH EXCIMER LASERS
AIP CONFERENCE PROCEEDINGS
1983: 143-150
View details for Web of Science ID A1983QZ37800019
- Measurement of Fast Melting and Regrowth Velocities in Picosecond Laser Heated Silicon Materials Research Society Symposium Proceedings edited by Narayan, J., Brown, W. L., Lemons, R. A. 1983
- Generation and Pulsewidth Measurement of Amplified Ultrashort Ultraviolet Laser Pulses in Krypton Fluoride Springer-Verlag series in Chemical Physics edited by Eisenthal, K. B., Hochstrasser, R. M., Kaiser, W., Laubereau, A. 1982
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AMPLIFICATION OF ULTRASHORT PULSES IN KRYPTON FLUORIDE AT 248-NM
OPTICS LETTERS
1982; 7 (9): 399-401
Abstract
Ultrashort pulses were produced at 248 nm by using a transverse-discharge KrF* excimer laser as a high-energy amplifier system. Input pulses for the amplifier system were obtained by upconverting the output of a modelocked visible dye laser to the ultraviolet by using nonlinear crystals. Pulses of up to 20 mJ; in energy with 10-30-psec duration were obtained at 10 pulses/sec. The output pulse width was characterized by using an electronic autocorrelator.
View details for Web of Science ID A1982PE07300002
View details for PubMedID 19714035
- A Picosecond, Tunable KrF* Excimer Laser Source Appl Phys. B 1982; 28: 128
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LASER GENERATION OF LIGHT IN THE EXTREME ULTRAVIOLET AND SOFT-X-RAY REGIME
AIP CONFERENCE PROCEEDINGS
1982: 491-494
View details for Web of Science ID A1982PW69800035
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PARITY NONCONSERVATION IN ATOMIC THALLIUM
SPRINGER. 1982: 280–81
View details for Web of Science ID A1982NS21600234
- Parity Violation in Atomic Physics Opportunities in Atomic and Molecular Science, Report by the Committee on Atomic and Molecular Science of the National Research Council 1982
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OBSERVATIONS OF PARITY NON-CONSERVATION IN ATOMIC THALLIUM
PHYSICAL REVIEW D
1981; 24 (5): 1134-1148
View details for Web of Science ID A1981ME35200006
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NEW OBSERVATION OF PARITY NON-CONSERVATION IN ATOMIC THALLIUM
PHYSICAL REVIEW LETTERS
1981; 46 (10): 640-643
View details for Web of Science ID A1981LE19100006
- Observation of Parity Nonconservation in Atomic Thallium Physical Review D 1981; 24: 1134
- New Observation of Parity Nonconservation in Atomic Thallium Physical Review Letters 1981; 46: 640
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THE PARITY NON-CONSERVING ELECTRON-NUCLEON INTERACTION
ANNUAL REVIEW OF NUCLEAR AND PARTICLE SCIENCE
1980; 30: 1-52
View details for Web of Science ID A1980KS66200001
- The Parity Nonconserving Electron-Nucleon Interaction Annual Reviews of Nuclear and Particle Science 1980; 30 (1)
- Preliminary Observation of Parity Nonconservation in Atomic Thallium Physical Review Letters 1979; 42: 343
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MAKING MICA RETARDATION PLATES - SIMPLE TECHNIQUE
APPLIED OPTICS
1979; 18 (8): 1138-1139
View details for Web of Science ID A1979GS20400009
View details for PubMedID 20208898
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PRELIMINARY OBSERVATION OF PARITY NON-CONSERVATION IN ATOMIC THALLIUM
PHYSICAL REVIEW LETTERS
1979; 42 (6): 343-346
View details for Web of Science ID A1979GG39100002
- Experimental Tests of Parity Nonconservation in Atomic Thallium Proceedings of the International Workshop on Neutral Current Interactions in Atoms edited by Williams, W. 1979: 92
- Electroproduction of K mesons along the virtual photon direction Physical Review D 1977; 15: 594