Bio


David earned his AB in Physics and AM in History of Science from Harvard in 1994, and his Ph.D. in Physics from the Massachusetts Institute of Technology in 1999, as a Hertz Fellow. During his Ph.D., David made the first demonstration of the Kondo effect in a semiconductor nanostructure. The Kondo effect is the interaction of a magnetic impurity atom with a surrounding metal host, and David's contribution enabled study of this classic system in a new and more tunable context, spurring a world-wide renaissance in this area. Also during this period, with colleagues at the MITRE Corporation he published an influential article examining the implications of novel nanoelectronic devices for computing. Following his Ph.D. he spent two years as a Junior Fellow in the Harvard Society of Fellows, then joined the faculty at Stanford University.

David has received a number of distinctions. In 2002, he received the inaugural George E. Valley Prize of the American Physical Society. This prize is awarded every 2-3 years to one early-career individual, for his or her outstanding contribution to the knowledge of physics. Also in 2002, he received the University of Illinois's McMillan Award in condensed matter physics, the premier recognition for a young condensed matter physicist. More recently he received the 2006 Award for Initiatives in Research from the National Academy of Sciences (one awarded per year), and a Packard Fellowship. He has also received young investigator awards from the Navy, Air Force, Sloan Foundation, Research Corporation, National Science Foundation, and Hellman Faculty Scholars program.

Academic Appointments


Administrative Appointments


  • Senator, Faculty Senate, Stanford University (2016 - 2020)
  • Chair, Faculty Senate Committee on Graduate Studies, Stanford University (2016 - 2018)
  • Professor of Physics with Tenure, Experimental Condensed Matter, Stanford University (2013 - Present)
  • Director, Center for Probing the Nanoscale, an NSF Nanoscale Science and engineering Center, Stanford University (2011 - 2014)
  • Associate Professor of Physics with Tenure, Experimental Condensed Matter, Stanford University (2008 - 2013)
  • Co-founder, Center for Probing the Nanoscale, Stanford University (2003 - Present)
  • Deputy Director, Center for Probing the Nanoscale, Stanford University (2003 - 2011)
  • Assistant Professor of Physics, Experimental Condensed Matter, Stanford University (2001 - 2008)
  • Member of Technical Staff, The MITRE Corporation (2000 - 2001)
  • Junior Fellow, Harvard Society of Fellows, Harvard University, Cambridge, MA (1999 - 2001)

Honors & Awards


  • Fellow, American Physical Society (2018)
  • Award for Excellence and Achievement, Center for Excellence in Education (2013)
  • Weston Visiting Professorship, Weizmann Institute (2010 - 2011)
  • Air Force Presidential (PECASE) Awardee, United States Air Force (2003 - 2007)
  • Young Investigator Award, Office of Naval Research (2001 - 2004)
  • Inaugural speaker for young investigator seminar, AFOSR/ONR (2007)
  • Research Innovation Award, Research Corporation (2004 - 2006)
  • Best paper by a young author, International Conference on Physics of Semiconductors (ICPS) (1998)
  • Best Paper, Review of nanoelectronic computing, MITRE Corp (1997)
  • Martin Deutsch Award, MIT (1997)
  • MIT Karl Taylor Compton PhD Fellow, MIT (1994 - 1996)
  • Hellman Faculty Scholar, Stanford University (2008)
  • David and Lucille Packard Fellowship, Packard Foundation (2004-2009)
  • Sloan Fellowship, Alfred P. Sloan Foundation (2003-2005)
  • Hertz PhD Fellow, Fannie and John Hertz Foundation (1994-1999)
  • Award for Initiatives in Research, National Academy of Sciences (2006)
  • Inaugural recipient of the George E. Valley Prize, American Physical Society (2002)
  • William McMillan Award, University of Illinois Urbana-Champaign, Department of Physics (2002)

Boards, Advisory Committees, Professional Organizations


  • Member, Selection Committee, George E. Valley Prize, American Physical Society (2004 - 2004)
  • Member, Selection Committee, Apker Award, American Physical Society (2006 - 2008)
  • Member, Selection Committee, William McMillan Award, University of Illinois (2007 - 2010)
  • Member, Stanford University Nanofabrication Facility Faculty Advisory Board (2005 - Present)
  • Member, Stanford University Engineering-Physics Faculty Group (2011 - Present)
  • Member, Stanford University Nanofacilities Committee (2008 - Present)
  • Director, Board of Directors, South Peninsula Hebrew Day School (2009 - 2015)
  • Member, University Graduate Study Committee, Stanford University (2014 - Present)
  • Chair, Graduate Study Committee, Physics Department, Stanford University (2008 - 2010)
  • Chair, Graduate Study Committee, Physics Department, Stanford University (2011 - 2013)
  • Chair, Condensed Matter Experiment Faculty Search Committee, Physics Department, Stanford University (2011 - Present)
  • Member, Long-range Planning Committee, Physics Department, Stanford University (2014 - Present)
  • Member, Undergraduate Study Committee, Stanford University (2008 - Present)
  • Member, Atomic, Molecular, and Optical Physics Faculty Search Committee, Stanford Univesity (2002 - 2008)
  • Member, Condensed Matter Theory Faculty Search Committee, Stanford University (2007 - 2009)
  • Member, Committee to Revamp the Freshmen Labs, Stanford University (2007 - 2008)
  • Member, Stanford University Nanofabrication Facility Executive Committee (2013 - Present)

Professional Education


  • PhD, Massachusetts Institute of Technology, Physics (1999)
  • AM, Harvard University, Cambridge, MA, History of Science (1994)
  • AB, Harvard University, Cambridge, MA, Physics (1994)

Current Research and Scholarly Interests


How do electrons organize themselves on the nanoscale?

We know that electrons are charged particles, and hence repel each other; yet in common metals like copper billions of electrons have plenty of room to maneuver and seem to move independently, taking no notice of each other. Professor Goldhaber-Gordon studies how electrons behave when they are instead confined to tiny structures, such as wires only tens of atoms wide. When constrained this way, electrons cannot easily avoid each other, and interactions strongly affect their organization and flow. The Goldhaber-Gordon group uses advanced fabrication techniques to confine electrons to semiconductor nanostructures, to extend our understanding of quantum mechanics to interacting particles, and to provide the basic science that will shape possible designs for future transistors and energy conversion technologies. The Goldhaber-Gordon group makes measurements using cryogenics, precision electrical measurements, and novel scanning probe techniques that allow direct spatial mapping of electron organization and flow. For some of their measurements of exotic quantum states, they cool electrons to a fiftieth of a degree above absolute zero, the world record for electrons in semiconductor nanostructures.

2019-20 Courses


Stanford Advisees


  • Doctoral Dissertation Reader (AC)
    Purnima Balakrishnan
  • Postdoctoral Faculty Sponsor
    Arthur Barnard, Evgeny Mikheev
  • Doctoral Dissertation Advisor (AC)
    Molly Andersen, John Bartel, Joe Finney, Eli Fox, Linsey Rodenbach, Ilan Rosen, Aaron Sharpe
  • Doctoral (Program)
    Matt Grant, Matthew Sorensen, Bai Yang Wang

All Publications


  • Signatures of tunable superconductivity in a trilayer graphene moire superlattice. Nature Chen, G., Sharpe, A. L., Gallagher, P., Rosen, I. T., Fox, E. J., Jiang, L., Lyu, B., Li, H., Watanabe, K., Taniguchi, T., Jung, J., Shi, Z., Goldhaber-Gordon, D., Zhang, Y., Wang, F. 2019

    Abstract

    Understanding the mechanism of high-transition-temperature (high-Tc) superconductivity is a central problem in condensed matter physics. It is often speculated that high-Tc superconductivity arises in a doped Mott insulator1 as described by the Hubbard model2-4. An exact solution of the Hubbard model, however, is extremely challenging owing to the strong electron-electron correlation in Mott insulators. Therefore, it is highly desirable to study a tunable Hubbard system, in which systematic investigations of the unconventional superconductivity and its evolution with the Hubbard parameters can deepen our understanding of the Hubbard model. Here we report signatures of tunable superconductivity in an ABC-trilayer graphene (TLG) and hexagonal boron nitride (hBN) moire superlattice. Unlike in 'magic angle' twisted bilayer graphene, theoretical calculations show that under a vertical displacement field, the ABC-TLG/hBN heterostructure features an isolated flat valence miniband associated with a Hubbard model on a triangular superlattice5,6 where the bandwidth can be tuned continuously with the vertical displacement field. Upon applying such a displacement field we find experimentally that the ABC-TLG/hBN superlattice displays Mott insulating states below 20 kelvin at one-quarter and one-half fillings of the states, corresponding to one and two holes per unit cell, respectively. Upon further cooling, signatures of superconductivity ('domes') emerge below 1 kelvin for the electron- and hole-doped sides of the one-quarter-filling Mott state. The electronic behaviour in the ABC-TLG/hBN superlattice is expected to depend sensitively on the interplay between the electron-electron interaction and the miniband bandwidth. By varying the vertical displacement field, we demonstrate transitions from the candidate superconductor to Mott insulator and metallic phases. Our study shows that ABC-TLG/hBN heterostructures offer attractive model systems in which to explore rich correlated behaviour emerging in the tunable triangular Hubbard model.

    View details for DOI 10.1038/s41586-019-1393-y

    View details for PubMedID 31316203

  • Emergent ferromagnetism near three-quarters filling in twisted bilayer graphene. Science (New York, N.Y.) Sharpe, A. L., Fox, E. J., Barnard, A. W., Finney, J., Watanabe, K., Taniguchi, T., Kastner, M. A., Goldhaber-Gordon, D. 2019

    Abstract

    When two sheets of graphene are stacked at a small twist angle, the resulting flat superlattice minibands are expected to strongly enhance electron-electron interactions. Here we present evidence that near three-quarters (3/4) filling of the conduction miniband these enhanced interactions drive the twisted bilayer graphene into a ferromagnetic state. In a narrow density range around an apparent insulating state at 3/4, we observe emergent ferromagnetic hysteresis, with a giant anomalous Hall (AH) effect as large as 10.4 kΩ and indications of chiral edge states. Surprisingly, the magnetization of the sample can be reversed by applying a small DC current. Although the AH resistance is not quantized and dissipation is significant, our measurements suggest that the system may be an incipient Chern insulator.

    View details for DOI 10.1126/science.aaw3780

    View details for PubMedID 31346139

  • Optical Imaging and Spectroscopic Characterization of Self-Assembled Environmental Adsorbates on Graphene NANO LETTERS Gallagher, P., Li, Y., Watanabe, K., Taniguchi, T., Heinz, T. F., Goldhaber-Gordon, D. 2018; 18 (4): 2603–8

    Abstract

    Topographic studies using scanning probes have found that graphene surfaces are often covered by micron-scale domains of periodic stripes with a 4 nm pitch. These stripes have been variously interpreted as structural ripples or as self-assembled adsorbates. We show that the stripe domains are optically anisotropic by imaging them using a polarization-contrast technique. Optical spectra between 1.1 and 2.8 eV reveal that the anisotropy in the in-plane dielectric function is predominantly real, reaching 0.6 for an assumed layer thickness of 0.3 nm. The spectra are incompatible with a rippled graphene sheet but would be quantitatively explained by the self-assembly of chainlike organic molecules into nanoscale stripes.

    View details for DOI 10.1021/acs.nanolett.8b00348

    View details for Web of Science ID 000430155900057

    View details for PubMedID 29589951

  • Chiral transport along magnetic domain walls in the quantum anomalous Hall effect NPJ QUANTUM MATERIALS Rosen, I. T., Fox, E. J., Kou, X., Pan, L., Wang, K. L., Goldhaber-Gordon, D. 2017; 2
  • Zero-field edge plasmons in a magnetic topological insulator NATURE COMMUNICATIONS Mahoney, A. C., Colless, J. I., Peeters, L., Pauka, S. J., Fox, E. J., Kou, X., Pan, L., Wang, K. L., Goldhaber-Gordon, D., Reilly, D. J. 2017; 8
  • Absorptive pinhole collimators for ballistic Dirac fermions in graphene NATURE COMMUNICATIONS Barnard, A. W., Hughes, A., Sharpe, A. L., Watanabe, K., Taniguchi, T., Goldhaber-Gordon, D. 2017; 8

    Abstract

    Ballistic electrons in solids can have mean free paths far larger than the smallest features patterned by lithography. This has allowed development and study of solid-state electron-optical devices such as beam splitters and quantum point contacts, which have informed our understanding of electron flow and interactions. Recently, high-mobility graphene has emerged as an ideal two-dimensional semimetal that hosts unique chiral electron-optical effects due to its honeycomb crystalline lattice. However, this chiral transport prevents the simple use of electrostatic gates to define electron-optical devices in graphene. Here we present a method of creating highly collimated electron beams in graphene based on collinear pairs of slits, with absorptive sidewalls between the slits. By this method, we achieve beams with angular width 18° or narrower, and transmission matching classical ballistic predictions.

    View details for DOI 10.1038/ncomms15418

    View details for Web of Science ID 000401279800001

    View details for PubMedID 28504264

  • Zero-field edge plasmons in a magnetic topological insulator. Nature communications Mahoney, A. C., Colless, J. I., Peeters, L., Pauka, S. J., Fox, E. J., Kou, X., Pan, L., Wang, K. L., Goldhaber-Gordon, D., Reilly, D. J. 2017; 8 (1): 1836

    Abstract

    Incorporating ferromagnetic dopants into three-dimensional topological insulator thin films has recently led to the realisation of the quantum anomalous Hall effect. These materials are of great interest since they may support electrical currents that flow without resistance, even at zero magnetic field. To date, the quantum anomalous Hall effect has been investigated using low-frequency transport measurements. However, transport results can be difficult to interpret due to the presence of parallel conductive paths, or because additional non-chiral edge channels may exist. Here we move beyond transport measurements by probing the microwave response of a magnetised disk of Cr-(Bi,Sb)2Te3. We identify features associated with chiral edge plasmons, a signature that robust edge channels are intrinsic to this material system. Our results provide a measure of the velocity of edge excitations without contacting the sample, and pave the way for an on-chip circuit element of practical importance: the zero-field microwave circulator.

    View details for PubMedID 29184065

  • Disorder from the Bulk Ionic Liquid in Electric Double Layer Transistors. ACS nano Petach, T. A., Reich, K. V., Zhang, X., Watanabe, K., Taniguchi, T., Shklovskii, B. I., Goldhaber-Gordon, D. 2017; 11 (8): 8395–8400

    Abstract

    Ionic liquid gating has a number of advantages over solid-state gating, especially for flexible or transparent devices and for applications requiring high carrier densities. However, the large number of charged ions near the channel inevitably results in Coulomb scattering, which limits the carrier mobility in otherwise clean systems. We develop a model for this Coulomb scattering. We validate our model experimentally using ionic liquid gating of graphene across varying thicknesses of hexagonal boron nitride, demonstrating that disorder in the bulk ionic liquid often dominates the scattering.

    View details for PubMedID 28753312

  • Robust fractional quantum Hall effect in the N=2 Landau level in bilayer graphene NATURE COMMUNICATIONS Diankov, G., Liang, C., Amet, F., Gallagher, P., Lee, M., Bestwick, A. J., Tharratt, K., Coniglio, W., Jaroszynski, J., Watanabe, K., Taniguchi, T., Goldhaber-Gordon, D. 2016; 7

    Abstract

    The fractional quantum Hall effect is a canonical example of electron-electron interactions producing new ground states in many-body systems. Most fractional quantum Hall studies have focussed on the lowest Landau level, whose fractional states are successfully explained by the composite fermion model. In the widely studied GaAs-based system, the composite fermion picture is thought to become unstable for the N≥2 Landau level, where competing many-body phases have been observed. Here we report magneto-resistance measurements of fractional quantum Hall states in the N=2 Landau level (filling factors 4<|ν|<8) in bilayer graphene. In contrast with recent observations of particle-hole asymmetry in the N=0/N=1 Landau levels of bilayer graphene, the fractional quantum Hall states we observe in the N=2 Landau level obey particle-hole symmetry within the fully symmetry-broken Landau level. Possible alternative ground states other than the composite fermions are discussed.

    View details for DOI 10.1038/ncomms13908

    View details for Web of Science ID 000390220800001

    View details for PubMedID 28000663

    View details for PubMedCentralID PMC5187585

  • Unconventional Correlation between Quantum Hall Transport Quantization and Bulk State Filling in Gated Graphene Devices PHYSICAL REVIEW LETTERS Cui, Y., Wen, B., Ma, E. Y., Diankov, G., Han, Z., Amet, F., Taniguchi, T., Watanabe, K., Goldhaber-Gordon, D., Dean, C. R., Shen, Z. 2016; 117 (18)

    Abstract

    We report simultaneous transport and scanning microwave impedance microscopy to examine the correlation between transport quantization and filling of the bulk Landau levels in the quantum Hall regime in gated graphene devices. Surprisingly, a comparison of these measurements reveals that quantized transport typically occurs below the complete filling of bulk Landau levels, when the bulk is still conductive. This result points to a revised understanding of transport quantization when carriers are accumulated by gating. We discuss the implications on transport study of the quantum Hall effect in graphene and related topological states in other two-dimensional electron systems.

    View details for DOI 10.1103/PhysRevLett.117.186601

    View details for Web of Science ID 000390227100011

    View details for PubMedID 27835026

  • Ballistic miniband conduction in a graphene superlattice. Science Lee, M., Wallbank, J. R., Gallagher, P., Watanabe, K., Taniguchi, T., Fal'ko, V. I., Goldhaber-Gordon, D. 2016; 353 (6307): 1526-1529

    Abstract

    Rational design of long-period artificial lattices yields effects unavailable in simple solids. The moiré pattern in highly aligned graphene/hexagonal boron nitride (h-BN) heterostructures is a lateral superlattice with high electron mobility and an unusual electronic dispersion whose miniband edges and saddle points can be reached by electrostatic gating. We investigated the dynamics of electrons in moiré minibands by measuring ballistic transport between adjacent local contacts in a magnetic field, known as the transverse electron focusing effect. At low temperatures, we observed caustics of skipping orbits extending over hundreds of superlattice periods, reversals of the cyclotron revolution for successive minibands, and breakdown of cyclotron motion near van Hove singularities. At high temperatures, electron-electron collisions suppress focusing. Probing such miniband conduction properties is a necessity for engineering novel transport behaviors in superlattice devices.

    View details for PubMedID 27708100

  • Voltage-Controlled Interfacial Layering in an Ionic Liquid on SrTiO3 ACS NANO Petach, T. A., Mehta, A., Marks, R., Johnson, B., Toney, M. F., Goldhaber-Gordon, D. 2016; 10 (4): 4565-4569

    Abstract

    One prominent structural feature of ionic liquids near surfaces is formation of alternating layers of anions and cations. However, how this layering responds to an applied potential is poorly understood. We focus on the structure of 1-butyl-1-methylpyrrolidinium tris(pentafluoroethyl) trifluorophosphate (BMPY-FAP) near the surface of a strontium titanate (SrTiO3) electric double-layer transistor. Using X-ray reflectivity, we show that at positive bias the individual layers in the ionic liquid double layer thicken and the layering persists further away from the interface. We model the reflectivity using a modified distorted crystal model with alternating cation and anion layers, which allows us to extract the charge density and the potential near the surface. We find that the charge density is strongly oscillatory with and without applied potential and that with an applied gate bias of 4.5 V the first two layers become significantly more cation rich than at zero bias, accumulating about 2.5 × 10(13) cm(-2) excess charge density.

    View details for DOI 10.1021/acsnano.6b00645

    View details for Web of Science ID 000375245000078

    View details for PubMedID 26959226

  • Switchable friction enabled by nanoscale self-assembly on graphene NATURE COMMUNICATIONS Gallagher, P., Lee, M., Amet, F., Maksymovych, P., Wang, J., Wang, S., Lu, X., Zhang, G., Watanabe, K., Taniguchi, T., Goldhaber-Gordon, D. 2016; 7

    Abstract

    Graphene monolayers are known to display domains of anisotropic friction with twofold symmetry and anisotropy exceeding 200%. This anisotropy has been thought to originate from periodic nanoscale ripples in the graphene sheet, which enhance puckering around a sliding asperity to a degree determined by the sliding direction. Here we demonstrate that these frictional domains derive not from structural features in the graphene but from self-assembly of environmental adsorbates into a highly regular superlattice of stripes with period 4-6 nm. The stripes and resulting frictional domains appear on monolayer and multilayer graphene on a variety of substrates, as well as on exfoliated flakes of hexagonal boron nitride. We show that the stripe-superlattices can be reproducibly and reversibly manipulated with submicrometre precision using a scanning probe microscope, allowing us to create arbitrary arrangements of frictional domains within a single flake. Our results suggest a revised understanding of the anisotropic friction observed on graphene and bulk graphite in terms of adsorbates.

    View details for DOI 10.1038/ncomms10745

    View details for Web of Science ID 000371037200007

    View details for PubMedID 26902595

    View details for PubMedCentralID PMC4766409

  • Universal Fermi liquid crossover and quantum criticality in a mesoscopic system. Nature Keller, A. J., Peeters, L., Moca, C. P., Weymann, I., Mahalu, D., Umansky, V., Zaránd, G., Goldhaber-Gordon, D. 2015; 526 (7572): 237-240

    View details for DOI 10.1038/nature15261

    View details for PubMedID 26450057

  • Precise Quantization of the Anomalous Hall Effect near Zero Magnetic Field PHYSICAL REVIEW LETTERS Bestwick, A. J., Fox, E. J., Kou, X., Pan, L., Wang, K. L., Goldhaber-Gordon, D. 2015; 114 (18)

    Abstract

    We report a nearly ideal quantum anomalous Hall effect in a three-dimensional topological insulator thin film with ferromagnetic doping. Near zero applied magnetic field we measure exact quantization in the Hall resistance to within a part per 10 000 and a longitudinal resistivity under 1  Ω per square, with chiral edge transport explicitly confirmed by nonlocal measurements. Deviations from this behavior are found to be caused by thermally activated carriers, as indicated by an Arrhenius law temperature dependence. Using the deviations as a thermometer, we demonstrate an unexpected magnetocaloric effect and use it to reach near-perfect quantization by cooling the sample below the dilution refrigerator base temperature in a process approximating adiabatic demagnetization refrigeration.

    View details for DOI 10.1103/PhysRevLett.114.187201

    View details for Web of Science ID 000353787800006

    View details for PubMedID 26001016

  • A high-mobility electronic system at an electrolyte-gated oxide surface NATURE COMMUNICATIONS Gallagher, P., Lee, M., Petach, T. A., Stanwyck, S. W., Williams, J. R., Watanabe, K., Taniguchi, T., Goldhaber-Gordon, D. 2015; 6

    Abstract

    Electrolyte gating is a powerful technique for accumulating large carrier densities at a surface. Yet this approach suffers from significant sources of disorder: electrochemical reactions can damage or alter the sample, and the ions of the electrolyte and various dissolved contaminants sit Angstroms from the electron system. Accordingly, electrolyte gating is well suited to studies of superconductivity and other phenomena robust to disorder, but of limited use when reactions or disorder must be avoided. Here we demonstrate that these limitations can be overcome by protecting the sample with a chemically inert, atomically smooth sheet of hexagonal boron nitride. We illustrate our technique with electrolyte-gated strontium titanate, whose mobility when protected with boron nitride improves more than 10-fold while achieving carrier densities nearing 10(14) cm(-2). Our technique is portable to other materials, and should enable future studies where high carrier density modulation is required but electrochemical reactions and surface disorder must be minimized.

    View details for DOI 10.1038/ncomms7437

    View details for Web of Science ID 000352633900021

    View details for PubMedID 25762485

  • Composite fermions and broken symmetries in graphene. Nature communications Amet, F., Bestwick, A. J., Williams, J. R., Balicas, L., Watanabe, K., Taniguchi, T., Goldhaber-Gordon, D. 2015; 6: 5838-?

    Abstract

    The electronic properties of graphene are described by a Dirac Hamiltonian with a four-fold symmetry of spin and valley. This symmetry may yield novel fractional quantum Hall (FQH) states at high magnetic field depending on the relative strength of symmetry-breaking interactions. However, observing such states in transport remains challenging in graphene, as they are easily destroyed by disorder. In this work, we observe in the first two Landau levels the two-flux composite-fermion sequences of FQH states between each integer filling factor. In particular, the odd-numerator fractions appear between filling factors 1 and 2, suggesting a broken-valley symmetry, consistent with our observation of a gap at charge neutrality and zero field. Contrary to our expectations, the evolution of gaps in a parallel magnetic field suggests that states in the first Landau level are not spin-polarized even up to very large out-of-plane fields.

    View details for DOI 10.1038/ncomms6838

    View details for PubMedID 25562690

  • Unexpected edge conduction in mercury telluride quantum wells under broken time-reversal symmetry. Nature communications Ma, E. Y., Calvo, M. R., Wang, J., Lian, B., Mühlbauer, M., Brüne, C., Cui, Y., Lai, K., Kundhikanjana, W., Yang, Y., Baenninger, M., König, M., Ames, C., Buhmann, H., Leubner, P., Molenkamp, L. W., Zhang, S., Goldhaber-Gordon, D., Kelly, M. A., Shen, Z. 2015; 6: 7252-?

    Abstract

    The realization of quantum spin Hall effect in HgTe quantum wells is considered a milestone in the discovery of topological insulators. Quantum spin Hall states are predicted to allow current flow at the edges of an insulating bulk, as demonstrated in various experiments. A key prediction yet to be experimentally verified is the breakdown of the edge conduction under broken time-reversal symmetry. Here we first establish a systematic framework for the magnetic field dependence of electrostatically gated quantum spin Hall devices. We then study edge conduction of an inverted quantum well device under broken time-reversal symmetry using microwave impedance microscopy, and compare our findings to a non-inverted device. At zero magnetic field, only the inverted device shows clear edge conduction in its local conductivity profile, consistent with theory. Surprisingly, the edge conduction persists up to 9 T with little change. This indicates physics beyond simple quantum spin Hall model, including material-specific properties and possibly many-body effects.

    View details for DOI 10.1038/ncomms8252

    View details for PubMedID 26006728

  • A high-mobility electronic system at an electrolyte-gated oxide surface. Nature communications Gallagher, P., Lee, M., Petach, T. A., Stanwyck, S. W., Williams, J. R., Watanabe, K., Taniguchi, T., Goldhaber-Gordon, D. 2015; 6: 6437-?

    Abstract

    Electrolyte gating is a powerful technique for accumulating large carrier densities at a surface. Yet this approach suffers from significant sources of disorder: electrochemical reactions can damage or alter the sample, and the ions of the electrolyte and various dissolved contaminants sit Angstroms from the electron system. Accordingly, electrolyte gating is well suited to studies of superconductivity and other phenomena robust to disorder, but of limited use when reactions or disorder must be avoided. Here we demonstrate that these limitations can be overcome by protecting the sample with a chemically inert, atomically smooth sheet of hexagonal boron nitride. We illustrate our technique with electrolyte-gated strontium titanate, whose mobility when protected with boron nitride improves more than 10-fold while achieving carrier densities nearing 10(14) cm(-2). Our technique is portable to other materials, and should enable future studies where high carrier density modulation is required but electrochemical reactions and surface disorder must be minimized.

    View details for DOI 10.1038/ncomms7437

    View details for PubMedID 25762485

  • Local imaging of high mobility two-dimensional electron systems with virtual scanning tunneling microscopy APPLIED PHYSICS LETTERS Pelliccione, M., BARTEL, J., Sciambi, A., Pfeiffer, L. N., West, K. W., Goldhaber-Gordon, D. 2014; 105 (18)

    View details for DOI 10.1063/1.4901174

    View details for Web of Science ID 000345000000024

  • Gate-tunable superconducting weak link and quantum point contact spectroscopy on a strontium titanate surface NATURE PHYSICS Gallagher, P., Lee, M., Williams, J. R., Goldhaber-Gordon, D. 2014; 10 (10): 748-752

    View details for DOI 10.1038/NPHYS3049

    View details for Web of Science ID 000343225200018

  • Emergent SU(4) Kondo physics in a spin-charge-entangled double quantum dot NATURE PHYSICS Keller, A. J., Amasha, S., Weymann, I., Moca, C. P., Rau, I. G., Katine, J. A., Shtrikman, H., Zarand, G., Goldhaber-Gordon, D. 2014; 10 (2): 145-150

    View details for DOI 10.1038/NPHYS2844

    View details for Web of Science ID 000332141800021

  • Insulating behavior at the neutrality point in single-layer graphene. Physical review letters Amet, F., Williams, J. R., Watanabe, K., Taniguchi, T., Goldhaber-Gordon, D. 2013; 110 (21): 216601-?

    Abstract

    The fate of the low-temperature conductance at the charge-neutrality (Dirac) point in a single sheet of graphene on boron nitride is investigated down to 20 mK. As the temperature is lowered, the peak resistivity diverges with a power-law behavior and becomes as high as several megohms per square at the lowest temperature, in contrast with the commonly observed saturation of the conductivity. As a perpendicular magnetic field is applied, our device remains insulating and directly transitions to the broken-valley-symmetry, ν=0 quantum Hall state, indicating that the insulating behavior we observe at zero magnetic field is a result of broken valley symmetry. Finally we discuss the possible origins of this effect.

    View details for PubMedID 23745906

  • Kondo effect in a single-electron transistor NATURE Goldhaber-Gordon, D., Shtrikman, H., Mahalu, D., Abusch-Magder, D., Meirav, U., Kastner, M. A. 1998; 391 (6663): 156-159
  • Visualization of an axion insulating state at the transition between 2 chiral quantum anomalous Hall states. Proceedings of the National Academy of Sciences of the United States of America Allen, M., Cui, Y., Yue Ma, E., Mogi, M., Kawamura, M., Fulga, I. C., Goldhaber-Gordon, D., Tokura, Y., Shen, Z. 2019

    Abstract

    Quantum-relativistic materials often host electronic phenomena with exotic spatial distributions. In particular, quantum anomalous Hall (QAH) insulators feature topological boundary currents whose chirality is determined by the magnetization orientation. However, understanding the microscopic nature of edge vs. bulk currents has remained a challenge due to the emergence of multidomain states at the phase transitions. Here we use microwave impedance microscopy (MIM) to directly image chiral edge currents and phase transitions in a magnetic topological insulator. Our images reveal a dramatic change in the edge state structure and an unexpected microwave response at the topological phase transition between the Chern number [Formula: see text] and [Formula: see text] states, consistent with the emergence of an insulating [Formula: see text] state. The magnetic transition width is independent of film thickness, but the transition pattern is distinct in differently initiated field sweeps. This behavior suggests that the [Formula: see text] state has 2 surface states with Hall conductivities of [Formula: see text] but with opposite signs.

    View details for DOI 10.1073/pnas.1818255116

    View details for PubMedID 31266887

  • Quantum-Hall to Insulator Transition in Ultra-Low-Carrier-Density Topological Insulator Films and a Hidden Phase of the Zeroth Landau Level. Advanced materials (Deerfield Beach, Fla.) Salehi, M., Shapourian, H., Rosen, I. T., Han, M., Moon, J., Shibayev, P., Jain, D., Goldhaber-Gordon, D., Oh, S. 2019: e1901091

    Abstract

    A key feature of the topological surface state under a magnetic field is the presence of the zeroth Landau level at the zero energy. Nonetheless, it is challenging to probe the zeroth Landau level due to large electron-hole puddles smearing its energy landscape. Here, by developing ultra-low-carrier density topological insulator Sb2 Te3 films, an extreme quantum limit of the topological surface state is reached and a hidden phase at the zeroth Landau level is uncovered. First, an unexpected quantum-Hall-to-insulator-transition near the zeroth Landau level is discovered. Then, through a detailed scaling analysis, it is found that this quantum-Hall-to-insulator-transition belongs to a new universality class, implying that the insulating phase discovered here has a fundamentally different origin from those in nontopological systems.

    View details for DOI 10.1002/adma.201901091

    View details for PubMedID 31259439

  • Significant Phonon Drag Enables High Power Factor in the AlGaN/GaN Two-Dimensional Electron Gas. Nano letters Yalamarthy, A. S., Munoz Rojo, M., Bruefach, A., Boone, D., Dowling, K. M., Satterthwaite, P. F., Goldhaber-Gordon, D., Pop, E., Senesky, D. G. 2019

    Abstract

    In typical thermoelectric energy harvesters and sensors, the Seebeck effect is caused by diffusion of electrons or holes in a temperature gradient. However, the Seebeck effect can also have a phonon drag component, due to momentum exchange between charge carriers and lattice phonons, which is more difficult to quantify. Here, we present the first study of phonon drag in the AlGaN/GaN two-dimensional electron gas (2DEG). We find that phonon drag does not contribute significantly to the thermoelectric behavior of devices with 100 nm GaN thickness, which suppresses the phonon mean free path. However, when the thickness is increased to 1.2 mum, up to 32% (88%) of the Seebeck coefficient at 300 K (50 K) can be attributed to the drag component. In turn, the phonon drag enables state-of-the-art thermoelectric power factor in the thicker GaN film, up to 40 mW m-1 K-2 at 50 K. By measuring the thermal conductivity of these AlGaN/GaN films, we show that the magnitude of the phonon drag can increase even when the thermal conductivity decreases. Decoupling of thermal conductivity and Seebeck coefficient could enable important advancements in thermoelectric power conversion with devices based on 2DEGs.

    View details for DOI 10.1021/acs.nanolett.9b00901

    View details for PubMedID 31088057

  • Absence of strong localization at low conductivity in the topological surface state of low-disorder Sb2Te3 PHYSICAL REVIEW B Rosen, I. T., Yudhistira, I., Sharma, G., Salehi, M., Kastner, M. A., Oh, S., Adam, S., Goldhaber-Gordon, D. 2019; 99 (20)
  • Using liquid electrolytes in dielectric reliability studies Lanza, M., Tang, K., Meng, A. C., Hui, F., Shi, Y., Han, T., Petach, T., Hitzman, C., Koh, A., Goldhaber-Gordon, D., McIntyre, P. C., IEEE IEEE. 2018
  • Crystal truncation rods from miscut surfaces PHYSICAL REVIEW B Petach, T. A., Mehta, A., Toney, M. F., Goldhaber-Gordon, D. 2017; 95 (18)
  • Temperature-dependent optical properties of titanium nitride APPLIED PHYSICS LETTERS Briggs, J. A., Naik, G. V., Zhao, Y., Petach, T. A., Sahasrabuddhe, K., Goldhaber-Gordon, D., Melosh, N. A., Dionne, J. A. 2017; 110 (10)

    View details for DOI 10.1063/1.4977840

    View details for Web of Science ID 000397871800011

  • Distinguishing Oxygen Vacancy Electromigration and Conductive Filament Formation in TiO2 Resistance Switching Using Liquid Electrolyte Contacts. Nano letters Tang, K., Meng, A. C., Hui, F., Shi, Y., Petach, T., Hitzman, C., Koh, A. L., Goldhaber-Gordon, D., Lanza, M., McIntyre, P. C. 2017; 17 (7): 4390–99

    Abstract

    Resistance switching in TiO2 and many other transition metal oxide resistive random access memory materials is believed to involve the assembly and breaking of interacting oxygen vacancy filaments via the combined effects of field-driven ion migration and local electronic conduction leading to Joule heating. These complex processes are very difficult to study directly in part because the filaments form between metallic electrode layers that block their observation by most characterization techniques. By replacing the top electrode layer in a metal-insulator-metal memory structure with easily removable liquid electrolytes, either an ionic liquid (IL) with high resistance contact or a conductive aqueous electrolyte, we probe field-driven oxygen vacancy redistribution in TiO2 thin films under conditions that either suppress or promote Joule heating. Oxygen isotope exchange experiments indicate that exchange of oxygen ions between TiO2 and the IL is facile at room temperature. Oxygen loss significantly increases the conductivity of the TiO2 films; however, filament formation is not observed after IL gating alone. Replacing the IL with a more conductive aqueous electrolyte contact and biasing does produce electroformed conductive filaments, consistent with a requirement for Joule heating to enhance the vacancy concentration and mobility at specific locations in the film.

    View details for PubMedID 28604007

  • Cotunneling Drag Effect in Coulomb-Coupled Quantum Dots. Physical review letters Keller, A. J., Lim, J. S., Sánchez, D., López, R., Amasha, S., Katine, J. A., Shtrikman, H., Goldhaber-Gordon, D. 2016; 117 (6): 066602-?

    Abstract

    In Coulomb drag, a current flowing in one conductor can induce a voltage across an adjacent conductor via the Coulomb interaction. The mechanisms yielding drag effects are not always understood, even though drag effects are sufficiently general to be seen in many low-dimensional systems. In this Letter, we observe Coulomb drag in a Coulomb-coupled double quantum dot and, through both experimental and theoretical arguments, identify cotunneling as essential to obtaining a correct qualitative understanding of the drag behavior.

    View details for DOI 10.1103/PhysRevLett.117.066602

    View details for PubMedID 27541473

  • Fully CMOS-compatible titanium nitride nanoantennas APPLIED PHYSICS LETTERS Briggs, J. A., Naik, G. V., Petach, T. A., Baum, B. K., Goldhaber-Gordon, D., Dionne, J. A. 2016; 108 (5)

    View details for DOI 10.1063/1.4941413

    View details for Web of Science ID 000373055700010

  • Resonant magneto-optic Kerr effect in the magnetic topological insulator Cr:(Sb-x,Bi1-x)(2)Te-3 PHYSICAL REVIEW B Patankar, S., Hinton, J. P., Griesmar, J., Orenstein, J., Dodge, J. S., Kou, X., Pan, L., Wang, K. L., Bestwick, A. J., Fox, E. J., Goldhaber-Gordon, D., Wang, J., Zhang, S. 2015; 92 (21)
  • Repairing nanoscale devices using electron-beam-induced deposition of platinum JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B Peeters, L., Keller, A. J., Umansky, V., Mahalu, D., Goldhaber-Gordon, D. 2015; 33 (5)

    View details for DOI 10.1116/1.4928718

    View details for Web of Science ID 000361833200029

  • Self-sensing cantilevers with integrated conductive coaxial tips for high-resolution electrical scanning probe metrology JOURNAL OF APPLIED PHYSICS Haemmerli, A. J., Harjee, N., Koenig, M., Garcia, A. G., Goldhaber-Gordon, D., Pruitt, B. L. 2015; 118 (3)

    View details for DOI 10.1063/1.4923231

    View details for Web of Science ID 000358429200024

  • Unexpected edge conduction in mercury telluride quantum wells under broken time-reversal symmetry NATURE COMMUNICATIONS Ma, E. Y., Calvo, M. R., Wang, J., Lian, B., Muehlbauer, M., Bruene, C., Cui, Y., Lai, K., Kundhikanjana, W., Yang, Y., Baenninger, M., Koenig, M., Ames, C., Buhmann, H., Leubner, P., Molenkamp, L. W., Zhang, S., Goldhaber-Gordon, D., Kelly, M. A., Shen, Z. 2015; 6

    Abstract

    The realization of quantum spin Hall effect in HgTe quantum wells is considered a milestone in the discovery of topological insulators. Quantum spin Hall states are predicted to allow current flow at the edges of an insulating bulk, as demonstrated in various experiments. A key prediction yet to be experimentally verified is the breakdown of the edge conduction under broken time-reversal symmetry. Here we first establish a systematic framework for the magnetic field dependence of electrostatically gated quantum spin Hall devices. We then study edge conduction of an inverted quantum well device under broken time-reversal symmetry using microwave impedance microscopy, and compare our findings to a non-inverted device. At zero magnetic field, only the inverted device shows clear edge conduction in its local conductivity profile, consistent with theory. Surprisingly, the edge conduction persists up to 9 T with little change. This indicates physics beyond simple quantum spin Hall model, including material-specific properties and possibly many-body effects.

    View details for DOI 10.1038/ncomms8252

    View details for Web of Science ID 000355539500001

    View details for PubMedID 26006728

    View details for PubMedCentralID PMC4455136

  • Mechanism for the large conductance modulation in electrolyte-gated thin gold films PHYSICAL REVIEW B Petach, T. A., Lee, M., Davis, R. C., Mehta, A., Goldhaber-Gordon, D. 2014; 90 (8)
  • Selective Equilibration of Spin-Polarized Quantum Hall Edge States in Graphene PHYSICAL REVIEW LETTERS Amet, F., Williams, J. R., Watanabe, K., Taniguchi, T., Goldhaber-Gordon, D. 2014; 112 (19)

    Abstract

    We report on transport measurements of dual-gated, single-layer graphene devices in the quantum Hall regime, allowing for independent control of the filling factors in adjoining regions. Progress in device quality allows us to study scattering between edge states when the fourfold degeneracy of the Landau level is lifted by electron correlations, causing edge states to be spin and/or valley polarized. In this new regime, we observe a dramatic departure from the equilibration seen in more disordered devices: edge states with opposite spins propagate without mixing. As a result, the degree of equilibration inferred from transport can reveal the spin polarization of the ground state at each filling factor. In particular, the first Landau level is shown to be spin polarized at half filling, providing an independent confirmation of a conclusion of Young et al. [Nat. Phys. 8, 550 (2012). The conductance in the bipolar regime is strongly suppressed, indicating that copropagating edge states, even with the same spin, do not equilibrate along PN interfaces. We attribute this behavior to the formation of an insulating ν = 0 stripe at the PN interface.

    View details for DOI 10.1103/PhysRevLett.112.196601

    View details for Web of Science ID 000335918900010

    View details for PubMedID 24877955

  • Universal conductance fluctuations in electrolyte-gated SrTiO3 nanostructures APPLIED PHYSICS LETTERS Stanwyck, S. W., Gallagher, P., Williams, J. R., Goldhaber-Gordon, D. 2013; 103 (21)

    View details for DOI 10.1063/1.4832555

    View details for Web of Science ID 000327590400084

  • Imaging currents in HgTe quantum wells in the quantum spin Hall regime. Nature materials Nowack, K. C., Spanton, E. M., Baenninger, M., König, M., Kirtley, J. R., Kalisky, B., Ames, C., Leubner, P., Brüne, C., Buhmann, H., Molenkamp, L. W., Goldhaber-Gordon, D., Moler, K. A. 2013; 12 (9): 787-791

    Abstract

    The quantum spin Hall (QSH) state is a state of matter characterized by a non-trivial topology of its band structure, and associated conducting edge channels. The QSH state was predicted and experimentally demonstrated to be realized in HgTe quantum wells. The existence of the edge channels has been inferred from local and non-local transport measurements in sufficiently small devices. Here we directly confirm the existence of the edge channels by imaging the magnetic fields produced by current flowing in large Hall bars made from HgTe quantum wells. These images distinguish between current that passes through each edge and the bulk. On tuning the bulk conductivity by gating or raising the temperature, we observe a regime in which the edge channels clearly coexist with the conducting bulk, providing input to the question of how ballistic transport may be limited in the edge channels. Our results represent a versatile method for characterization of new QSH materials systems.

    View details for DOI 10.1038/nmat3682

    View details for PubMedID 23770727

  • Imaging currents in HgTe quantum wells in the quantum spin Hall regime. Nature materials Nowack, K. C., Spanton, E. M., Baenninger, M., König, M., Kirtley, J. R., Kalisky, B., Ames, C., Leubner, P., Brüne, C., Buhmann, H., Molenkamp, L. W., Goldhaber-Gordon, D., Moler, K. A. 2013; 12 (9): 787-791

    Abstract

    The quantum spin Hall (QSH) state is a state of matter characterized by a non-trivial topology of its band structure, and associated conducting edge channels. The QSH state was predicted and experimentally demonstrated to be realized in HgTe quantum wells. The existence of the edge channels has been inferred from local and non-local transport measurements in sufficiently small devices. Here we directly confirm the existence of the edge channels by imaging the magnetic fields produced by current flowing in large Hall bars made from HgTe quantum wells. These images distinguish between current that passes through each edge and the bulk. On tuning the bulk conductivity by gating or raising the temperature, we observe a regime in which the edge channels clearly coexist with the conducting bulk, providing input to the question of how ballistic transport may be limited in the edge channels. Our results represent a versatile method for characterization of new QSH materials systems.

    View details for DOI 10.1038/nmat3682

    View details for PubMedID 23770727

  • Direct measurement of current-phase relations in superconductor/topological insulator/superconductor junctions. Nano letters Sochnikov, I., Bestwick, A. J., Williams, J. R., Lippman, T. M., Fisher, I. R., Goldhaber-Gordon, D., Kirtley, J. R., Moler, K. A. 2013; 13 (7): 3086-3092

    Abstract

    Proximity to a superconductor is predicted to induce exotic quantum phases in topological insulators. Here, scanning superconducting quantum interference device (SQUID) microscopy reveals that aluminum superconducting rings with topologically insulating Bi2Se3 junctions exhibit a conventional, nearly sinusoidal 2π-periodic current-phase relations. Pearl vortices occur in longer junctions, indicating suppressed superconductivity in aluminum, probably due to a proximity effect. Our observations establish scanning SQUID as a general tool for characterizing proximity effects and for measuring current-phase relations in new materials systems.

    View details for DOI 10.1021/nl400997k

    View details for PubMedID 23795666

  • Direct Measurement of Current-Phase Relations in Superconductor/Topological Insulator/Superconductor Junctions NANO LETTERS Sochnikov, I., Bestwick, A. J., Williams, J. R., Lippman, T. M., Fisher, I. R., Godhaber-Gordon, D., Kirtley, J. R., Moler, K. A. 2013; 13 (7): 3086-3092

    Abstract

    Proximity to a superconductor is predicted to induce exotic quantum phases in topological insulators. Here, scanning superconducting quantum interference device (SQUID) microscopy reveals that aluminum superconducting rings with topologically insulating Bi2Se3 junctions exhibit a conventional, nearly sinusoidal 2π-periodic current-phase relations. Pearl vortices occur in longer junctions, indicating suppressed superconductivity in aluminum, probably due to a proximity effect. Our observations establish scanning SQUID as a general tool for characterizing proximity effects and for measuring current-phase relations in new materials systems.

    View details for DOI 10.1021/nl400997k

    View details for Web of Science ID 000321884300014

  • Insulating Behavior at the Neutrality Point in Single-Layer Graphene PHYSICAL REVIEW LETTERS Amet, F., Williams, J. R., Watanabe, K., Taniguchi, T., Goldhaber-Gordon, D. 2013; 110 (21)

    Abstract

    The fate of the low-temperature conductance at the charge-neutrality (Dirac) point in a single sheet of graphene on boron nitride is investigated down to 20 mK. As the temperature is lowered, the peak resistivity diverges with a power-law behavior and becomes as high as several megohms per square at the lowest temperature, in contrast with the commonly observed saturation of the conductivity. As a perpendicular magnetic field is applied, our device remains insulating and directly transitions to the broken-valley-symmetry, ν=0 quantum Hall state, indicating that the insulating behavior we observe at zero magnetic field is a result of broken valley symmetry. Finally we discuss the possible origins of this effect.

    View details for DOI 10.1103/PhysRevLett.110.216601

    View details for Web of Science ID 000319278400015

    View details for PubMedID 23745906

  • Spatially Resolved Study of Backscattering in the Quantum Spin Hall State PHYSICAL REVIEW X Koenig, M., Baenninger, M., Garcia, A. G., Harjee, N., Pruitt, B. L., Ames, C., Leubner, P., Bruene, C., Buhmann, H., Molenkamp, L. W., Goldhaber-Gordon, D. 2013; 3 (2)
  • Design of a scanning gate microscope for mesoscopic electron systems in a cryogen-free dilution refrigerator. Review of scientific instruments Pelliccione, M., Sciambi, A., BARTEL, J., Keller, A. J., Goldhaber-Gordon, D. 2013; 84 (3): 033703-?

    Abstract

    We report on our design of a scanning gate microscope housed in a cryogen-free dilution refrigerator with a base temperature of 15 mK. The recent increase in efficiency of pulse tube cryocoolers has made cryogen-free systems popular in recent years. However, this new style of cryostat presents challenges for performing scanning probe measurements, mainly as a result of the vibrations introduced by the cryocooler. We demonstrate scanning with root-mean-square vibrations of 0.8 nm at 3 K and 2.1 nm at 15 mK in a 1 kHz bandwidth with our design. Using Coulomb blockade thermometry on a GaAs/AlGaAs gate-defined quantum dot, we demonstrate an electron temperature of 45 mK.

    View details for DOI 10.1063/1.4794767

    View details for PubMedID 23556823

  • Design of a scanning gate microscope for mesoscopic electron systems in a cryogen-free dilution refrigerator REVIEW OF SCIENTIFIC INSTRUMENTS Pelliccione, M., Sciambi, A., BARTEL, J., Keller, A. J., Goldhaber-Gordon, D. 2013; 84 (3)

    View details for DOI 10.1063/1.4794767

    View details for Web of Science ID 000316966200023

    View details for PubMedID 23556823

  • Scanning gate microscopy of localized states in wide graphene constrictions PHYSICAL REVIEW B Garcia, A. G., Koenig, M., Goldhaber-Gordon, D., Todd, K. 2013; 87 (8)
  • Extreme Mono layer-Selectivity of Hydrogen-Plasma Reactions with Graphene ACS NANO Diankov, G., Neumann, M., Goldhaber-Gordon, D. 2013; 7 (2): 1324-1332

    Abstract

    We study the effect of remote hydrogen plasma on graphene deposited on SiO₂. We observe strong monolayer selectivity for reactions with plasma species, characterized by isotropic hole formation in the basal plane of monolayers and etching from the sheet edges. The areal density of etch pits on monolayers is 2 orders of magnitude higher than on bilayers or thicker sheets. For bilayer or thicker sheets, the etch pit morphology is also quite different: hexagonal etch pits of uniform size, indicating that etching is highly anisotropic and proceeds from pre-existing defects rather than nucleating continuously as on monolayers. The etch rate displays a pronounced dependence on sample temperature for monolayer and multilayer graphene alike: very slow at room temperature, peaking at 400 °C and suppressed entirely at 700 °C. Applying the same hydrogen plasma treatment to graphene deposited on the much smoother substrate mica leads to very similar phenomenology as on the rougher SiO₂, suggesting that a factor other than substrate roughness controls the reactivity of monolayer graphene with hydrogen plasma species.

    View details for DOI 10.1021/nn304903m

    View details for Web of Science ID 000315618700050

    View details for PubMedID 23327591

  • Pseudospin-Resolved Transport Spectroscopy of the Kondo Effect in a Double Quantum Dot PHYSICAL REVIEW LETTERS Amasha, S., Keller, A. J., Rau, I. G., Carmi, A., Katine, J. A., Shtrikman, H., Oreg, Y., Goldhaber-Gordon, D. 2013; 110 (4)
  • Fabrication of samples for scanning probe experiments on quantum spin Hall effect in HgTe quantum wells JOURNAL OF APPLIED PHYSICS Baenninger, M., Koenig, M., Garcia, A. G., Muehlbauer, M., Ames, C., Leubner, P., Bruene, C., Buhmann, H., Molenkamp, L. W., Goldhaber-Gordon, D. 2012; 112 (10)

    View details for DOI 10.1063/1.4767362

    View details for Web of Science ID 000311969800069

  • MAJORANA FERMIONS Doubling down on Majorana NATURE PHYSICS Williams, J. R., Goldhaber-Gordon, D. 2012; 8 (11): 778-779

    View details for DOI 10.1038/nphys2459

    View details for Web of Science ID 000310836700006

  • Molecular Junctions of Self-Assembled Monolayers with Conducting Polymer Contacts ACS NANO Neuhausen, A. B., Hosseini, A., Sulpizio, J. A., Chidsey, C. E., Goldhaber-Gordon, D. 2012; 6 (11): 9920-9931

    Abstract

    We present a method to fabricate individually addressable junctions of self-assembled monolayers (SAMs) that builds on previous studies which have shown that soft conductive polymer top contacts virtually eliminate shorts through the SAMs. We demonstrate devices with nanoscale lateral dimensions, representing an order of magnitude reduction in device area, with high yield and relatively low device-to-device variation, improving several features of previous soft contact devices. The devices are formed in pores in an inorganic dielectric layer with features defined by e-beam lithography and dry etching. We replace the aqueous PEDOT:PSS conductive polymer used in prior devices with Aedotron P, a low-viscosity, amphiphilic polymer, allowing incorporation of self-assembled monolayers with either hydrophobic or hydrophilic termination with the same junction geometry and materials. We demonstrate the adaptability of this new design by presenting transport measurements on SAMs composed of alkanethiols with methyl, thiol, carboxyl, and azide terminations. We establish that the observed room-temperature tunnel barrier is primarily a function of monolayer thickness, independent of the terminal group's hydrophilicity. Finally, we investigate the temperature dependence of transport and show that the low-temperature behavior is based on the energy distribution of sites from which carriers can tunnel between the polymer and gold contacts, as described by a model of variable-range hopping transport in a disordered conductor.

    View details for DOI 10.1021/nn3035183

    View details for Web of Science ID 000311521700061

    View details for PubMedID 23035989

  • Quantum oscillations from a two-dimensional electron gas at a Mott/band insulator interface APPLIED PHYSICS LETTERS Moetakef, P., Ouellette, D. G., Williams, J. R., Allen, S. J., Balents, L., Goldhaber-Gordon, D., Stemmer, S. 2012; 101 (15)

    View details for DOI 10.1063/1.4758989

    View details for Web of Science ID 000310304900028

  • Transmission phase shifts of Kondo impurities PHYSICAL REVIEW B Carmi, A., Oreg, Y., Berkooz, M., Goldhaber-Gordon, D. 2012; 86 (11)
  • Effective Cleaning of Hexagonal Boron Nitride for Graphene Devices NANO LETTERS Garcia, A. G., Neumann, M., Amet, F., Williams, J. R., Watanabe, K., Taniguchi, T., Goldhaber-Gordon, D. 2012; 12 (9): 4449-4454

    Abstract

    Hexagonal boron nitride (h-BN) films have attracted considerable interest as substrates for graphene. ( Dean, C. R. et al. Nat. Nanotechnol. 2010 , 5 , 722 - 6 ; Wang, H. et al. Electron Device Lett. 2011 , 32 , 1209 - 1211 ; Sanchez-Yamagishi, J. et al. Phys. Rev. Lett. 2012 , 108 , 1 - 5 .) We study the presence of organic contaminants introduced by standard lithography and substrate transfer processing on h-BN films exfoliated on silicon oxide substrates. Exposure to photoresist processing adds a large broad luminescence peak to the Raman spectrum of the h-BN flake. This signal persists through typical furnace annealing recipes (Ar/H(2)). A recipe that successfully removes organic contaminants and results in clean h-BN flakes involves treatment in Ar/O(2) at 500 °C.

    View details for DOI 10.1021/nl3011726

    View details for Web of Science ID 000308576000006

    View details for PubMedID 22866696

  • Unconventional Josephson Effect in Hybrid Superconductor-Topological Insulator Devices PHYSICAL REVIEW LETTERS Williams, J. R., Bestwick, A. J., Gallagher, P., Hong, S. S., Cui, Y., Bleich, A. S., Analytis, J. G., Fisher, I. R., Goldhaber-Gordon, D. 2012; 109 (5)

    Abstract

    We report on transport properties of Josephson junctions in hybrid superconducting-topological insulator devices, which show two striking departures from the common Josephson junction behavior: a characteristic energy that scales inversely with the width of the junction, and a low characteristic magnetic field for suppressing supercurrent. To explain these effects, we propose a phenomenological model which expands on the existing theory for topological insulator Josephson junctions.

    View details for DOI 10.1103/PhysRevLett.109.056803

    View details for Web of Science ID 000306944200002

    View details for PubMedID 23006196

  • Carrier-Controlled Ferromagnetism in SrTiO3 PHYSICAL REVIEW X Moetakef, P., Williams, J. R., Ouellette, D. G., Kajdos, A. P., Goldhaber-Gordon, D., Allen, S. J., Stemmer, S. 2012; 2 (2)
  • Low-impedance shielded tip piezoresistive probe enables portable microwave impedance microscopy MICRO & NANO LETTERS Haemmerli, A. J., Nielsen, R. T., Kundhikanjana, W., HARJEE, N., Goldhaber-Gordon, D., Shen, Z. X., Pruitt, B. L. 2012; 7 (4): 321-324
  • Tunneling spectroscopy of graphene-boron-nitride heterostructures PHYSICAL REVIEW B Amet, F., Williams, J. R., Garcia, A. G., Yankowitz, M., Watanabe, K., Taniguchi, T., Goldhaber-Gordon, D. 2012; 85 (7)
  • LOW-IMPEDANCE SHIELDED TIP PIEZORESISTIVE PROBE ENABLES PORTABLE MICROWAVE IMPEDANCE MICROSCOPY 25th IEEE International Conference on Micro Electro Mechanical Systems (MEMS) Haemmerli, A. J., Nielsen, R. T., Kundhikanjana, W., HARJEE, N., Lai, K., Yang, Y. L., Goldhaber-Gordon, D., Shen, Z. X., Pruitt, B. L. IEEE. 2012
  • Spin-1/2 Kondo effect in an InAs nanowire quantum dot: Unitary limit, conductance scaling, and Zeeman splitting PHYSICAL REVIEW B Kretinin, A. V., Shtrikman, H., Goldhaber-Gordon, D., Hanl, M., Weichselbaum, A., von Delft, J., Costi, T., Mahalu, D. 2011; 84 (24)
  • Electrolyte Gate-Controlled Kondo Effect in SrTiO3 PHYSICAL REVIEW LETTERS Lee, M., Williams, J. R., Zhang, S., Frisbie, C. D., Goldhaber-Gordon, D. 2011; 107 (25)

    Abstract

    We report low-temperature, high-field magnetotransport measurements of SrTiO(3) gated by an ionic gel electrolyte. A saturating resistance upturn and negative magnetoresistance that signal the emergence of the Kondo effect appear for higher applied gate voltages. This observation, enabled by the wide tunability of the ionic gel-applied electric field, promotes the interpretation of the electric field-effect-induced 2D electron system in SrTiO(3) as an admixture of magnetic Ti(3+) ions, i.e., localized and unpaired electrons, and delocalized electrons that partially fill the Ti 3d conduction band.

    View details for DOI 10.1103/PhysRevLett.107.256601

    View details for PubMedID 22243097

  • An integrated capacitance bridge for high-resolution, wide temperature range quantum capacitance measurements (vol 82, 053904, 2011) REVIEW OF SCIENTIFIC INSTRUMENTS Hazeghi, A., Sulpizio, J. A., Diankov, G., Goldhaber-Gordon, D., Wong, H. S. 2011; 82 (12)

    View details for DOI 10.1063/1.3665097

    View details for Web of Science ID 000298643100076

  • Coulomb Blockade in an Open Quantum Dot PHYSICAL REVIEW LETTERS Amasha, S., Rau, I. G., Grobis, M., Potok, R. M., Shtrikman, H., Goldhaber-Gordon, D. 2011; 107 (21)

    Abstract

    We report the observation of Coulomb blockade in a quantum dot contacted by two quantum point contacts each with a single fully transmitting mode, a system thought to be well described without invoking Coulomb interactions. Below 50 mK we observe a periodic oscillation in the conductance of the dot with gate voltage, corresponding to a residual quantization of charge. From the temperature and magnetic field dependence, we infer the oscillations are mesoscopic Coulomb blockade, a type of Coulomb blockade caused by electron interference in an otherwise open system.

    View details for DOI 10.1103/PhysRevLett.107.216804

    View details for Web of Science ID 000297136400007

    View details for PubMedID 22181909

  • Vertical field-effect transistor based on wave-function extension PHYSICAL REVIEW B Sciambi, A., Pelliccione, M., Lilly, M. P., Bank, S. R., Gossard, A. C., Pfeiffer, L. N., West, K. W., Goldhaber-Gordon, D. 2011; 84 (8)
  • An integrated capacitance bridge for high-resolution, wide temperature range quantum capacitance measurements REVIEW OF SCIENTIFIC INSTRUMENTS Hazeghi, A., Sulpizio, J. A., Diankov, G., Goldhaber-Gordon, D., Wong, H. S. 2011; 82 (5)

    Abstract

    We have developed a highly sensitive integrated capacitance bridge for quantum capacitance measurements. Our bridge, based on a GaAs HEMT amplifier, delivers attofarad (aF) resolution using a small AC excitation at or below k(B)T over a broad temperature range (4-300 K). We have achieved a resolution at room temperature of 60 aF/√Hz for a 10  mV ac excitation at 17.5 kHz, with an improved resolution at cryogenic temperatures, for the same excitation amplitude. We demonstrate the utility of our bridge for measuring the quantum capacitance of nanostructures by measuring the capacitance of top-gated graphene devices and cleanly resolving the density of states.

    View details for DOI 10.1063/1.3582068

    View details for PubMedID 21639515

  • NANOELECTRONICS Making light of electrons NATURE NANOTECHNOLOGY Goldhaber-Gordon, D. 2011; 6 (4): 196-197

    Abstract

    Electrons have been channelled through graphene wires using the principles of optical guiding by fibre optic cables.

    View details for DOI 10.1038/nnano.2011.53

    View details for Web of Science ID 000289199700003

    View details for PubMedID 21468106

  • Virtual scanning tunneling microscopy: A local spectroscopic probe of two-dimensional electron systems (vol 97, 132103, 2010) APPLIED PHYSICS LETTERS Sciambi, A., Pelliccione, M., Bank, S. R., Gossard, A. C., Goldhaber-Gordon, D. 2011; 98 (8)

    View details for DOI 10.1063/1.3554334

    View details for Web of Science ID 000287764300099

  • Local interlayer tunneling between two-dimensional electron systems in the ballistic regime PHYSICAL REVIEW B Luna, K., Kim, E., Oreto, P., Kivelson, S. A., Goldhaber-Gordon, D. 2010; 82 (23)
  • Dip-Pen Nanolithography of Electrical Contacts to Single Graphene Flakes ACS NANO Wang, W. M., Stander, N., Stoltenberg, R. M., Goldhaber-Gordon, D., Bao, Z. 2010; 4 (11): 6409-6416

    Abstract

    This study evaluates an alternative to electron-beam lithography for fabricating nanoscale graphene devices. Dip-pen nanolithography is used for defining monolayer graphene flakes and for patterning of gold electrodes through writing of an alkylthiol on thin films of gold evaporated onto graphene flakes. A wet gold etching step was used to form the individual devices. The sheet resistances of these monolayer graphene devices are comparable to reported literature values. This alternative technique for making electrical contact to 2D nanostructures provides a platform for fundamental studies of nanomaterial properties. The merits of using dip-pen nanolithography include lack of electron-beam irradiation damage and targeted patterning of individual devices with imaging and writing conducted in the same instrument under ambient conditions.

    View details for DOI 10.1021/nn101324x

    View details for Web of Science ID 000284438000015

    View details for PubMedID 20945878

  • Spatially probed electron-electron scattering in a two-dimensional electron gas PHYSICAL REVIEW B Jura, M. P., Grobis, M., Topinka, M. A., Pfeiffer, L. N., West, K. W., Goldhaber-Gordon, D. 2010; 82 (15)
  • Virtual scanning tunneling microscopy: A local spectroscopic probe of two-dimensional electron systems APPLIED PHYSICS LETTERS Sciambi, A., Pelliccione, M., Bank, S. R., Gossard, A. C., Goldhaber-Gordon, D. 2010; 97 (13)

    View details for DOI 10.1063/1.3492440

    View details for Web of Science ID 000282443800035

  • Observation of a one-dimensional spin-orbit gap in a quantum wire NATURE PHYSICS Quay, C. H., Hughes, T. L., Sulpizio, J. A., Pfeiffer, L. N., Baldwin, K. W., West, K. W., Goldhaber-Gordon, D., de Picciotto, R. 2010; 6 (5): 336-339

    View details for DOI 10.1038/NPHYS1626

    View details for Web of Science ID 000278335500011

  • Magnetic Doping and Kondo Effect in Bi2Se3 Nanoribbons NANO LETTERS Cha, J. J., Williams, J. R., Kong, D., Meister, S., Peng, H., Bestwick, A. J., Gallagher, P., Goldhaber-Gordon, D., Cui, Y. 2010; 10 (3): 1076-1081

    Abstract

    A simple surface band structure and a large bulk band gap have allowed Bi2Se3 to become a reference material for the newly discovered three-dimensional topological insulators, which exhibit topologically protected conducting surface states that reside inside the bulk band gap. Studying topological insulators such as Bi2Se3 in nanostructures is advantageous because of the high surface-to-volume ratio, which enhances effects from the surface states; recently reported Aharonov-Bohm oscillation in topological insulator nanoribbons by some of us is a good example. Theoretically, introducing magnetic impurities in topological insulators is predicted to open a small gap in the surface states by breaking time-reversal symmetry. Here, we present synthesis of magnetically doped Bi2Se3 nanoribbons by vapor-liquid-solid growth using magnetic metal thin films as catalysts. Although the doping concentration is less than approximately 2%, low-temperature transport measurements of the Fe-doped Bi2Se3 nanoribbon devices show a clear Kondo effect at temperatures below 30 K, confirming the presence of magnetic impurities in the Bi2Se3 nanoribbons. The capability to dope topological insulator nanostructures magnetically opens up exciting opportunities for spintronics.

    View details for DOI 10.1021/nl100146n

    View details for Web of Science ID 000275278200057

    View details for PubMedID 20131918

  • Disorder-induced gap behavior in graphene nanoribbons PHYSICAL REVIEW B Gallagher, P., Todd, K., Goldhaber-Gordon, D. 2010; 81 (11)
  • COAXIAL TIP PIEZORESISTIVE SCANNING PROBES FOR HIGH-RESOLUTION ELECTRICAL IMAGING 23rd IEEE International Conference on Micro Electro Mechanical Systems (MEMS 2010) HARJEE, N., Garcia, A. G., Koenig, M., Doll, J. C., Goldhaber-Gordon, D., Pruitt, B. L. IEEE. 2010: 344–347
  • Coaxial Tip Piezoresistive Scanning Probes with Sub-Nanometer Vertical Displacement Resolution 2010 IEEE Sensors Conference Harjee, N., Haemmerli, A., Goldhaber-Gordon, D., Pruitt, B. L. IEEE. 2010: 1962–1966
  • Electron interferometer formed with a scanning probe tip and quantum point contact PHYSICAL REVIEW B Jura, M. P., Topinka, M. A., Grobis, M., Pfeiffer, L. N., West, K. W., Goldhaber-Gordon, D. 2009; 80 (4)
  • Charge Transport in Interpenetrating Networks of Semiconducting and Metallic Carbon Nanotubes NANO LETTERS Topinka, M. A., Rowell, M. W., Goldhaber-Gordon, D., McGehee, M. D., Hecht, D. S., Gruner, G. 2009; 9 (5): 1866-1871

    Abstract

    Carbon nanotube network field effect transistors (CNTN-FETs) are promising candidates for low cost macroelectronics. We investigate the microscopic transport in these devices using electric force microscopy and simulations. We find that in many CNTN-FETs the voltage drops abruptly at a point in the channel where the current is constricted to just one tube. We also model the effect of varying the semiconducting/metallic tube ratio. The effect of Schottky barriers on both conductance within semiconducting tubes and conductance between semiconducting and metallic tubes results in three possible types of CNTN-FETs with fundamentally different gating mechanisms. We describe this with an electronic phase diagram.

    View details for DOI 10.1021/nl803849e

    View details for Web of Science ID 000266157100025

    View details for PubMedID 19331424

  • Contact resistance and shot noise in graphene transistors PHYSICAL REVIEW B Cayssol, J., Huard, B., Goldhaber-Gordon, D. 2009; 79 (7)
  • Evidence for Klein Tunneling in Graphene p-n Junctions PHYSICAL REVIEW LETTERS Stander, N., Huard, B., Goldhaber-Gordon, D. 2009; 102 (2)

    Abstract

    Transport through potential barriers in graphene is investigated using a set of metallic gates capacitively coupled to graphene to modulate the potential landscape. When a gate-induced potential step is steep enough, disorder becomes less important and the resistance across the step is in quantitative agreement with predictions of Klein tunneling of Dirac fermions up to a small correction. We also perform magnetoresistance measurements at low magnetic fields and compare them to recent predictions.

    View details for DOI 10.1103/PhysRevLett.102.026807

    View details for Web of Science ID 000262535900059

    View details for PubMedID 19257307

  • Quantum Dot Behavior in Graphene Nanoconstrictions NANO LETTERS Todd, K., Chou, H., Amasha, S., Goldhaber-Gordon, D. 2009; 9 (1): 416-421

    Abstract

    Graphene nanoribbons display an imperfectly understood transport gap. We measure transport through nanoribbon devices of several lengths. In long (>/=250 nm) nanoribbons we observe transport through multiple quantum dots in series, while shorter (

    View details for DOI 10.1021/nl803291b

    View details for Web of Science ID 000262519100076

    View details for PubMedID 19099454

  • Evidence of the role of contacts on the observed electron-hole asymmetry in graphene PHYSICAL REVIEW B Huard, B., Stander, N., Sulpizio, J. A., Goldhaber-Gordon, D. 2008; 78 (12)
  • An off-board quantum point contact as a sensitive detector of cantilever motion NATURE PHYSICS Poggio, M., Jura, M. P., Degen, C. L., Topinka, M. A., Mamin, H. J., Goldhaber-Gordon, D., Rugar, D. 2008; 4 (8): 635-638

    View details for DOI 10.1038/nphys992

    View details for Web of Science ID 000258326000016

  • Universal scaling in nonequilibrium transport through a single channel Kondo dot PHYSICAL REVIEW LETTERS Grobis, M., Rau, I. G., Potok, R. M., Shtrikman, H., Goldhaber-Gordon, D. 2008; 100 (24)

    Abstract

    Scaling laws and universality play an important role in our understanding of critical phenomena and the Kondo effect. We present measurements of nonequilibrium transport through a single-channel Kondo quantum dot at low temperature and bias. We find that the low-energy Kondo conductance is consistent with universality between temperature and bias and is characterized by a quadratic scaling exponent, as expected for the spin-1/2 Kondo effect. We show that the nonequilibrium Kondo transport measurements are well described by a universal scaling function with two scaling parameters.

    View details for DOI 10.1103/PhysRevLett.100.246601

    View details for Web of Science ID 000256942400052

    View details for PubMedID 18643605

  • Electron thermal microscopy NANO LETTERS Brintlinger, T., Qi, Y., Baloch, K. H., Goldhaber-Gordon, D., Cumings, J. 2008; 8 (2): 582-585

    Abstract

    We present real-time, nanoscale temperature mapping using a transmission electron microscope and standard phase transitions in metal islands. Islands are deposited on the reverse side of commercially available silicon nitride membranes, while local thermal gradients are produced by Joule heating in a thin wire on the front side of the membrane. Change in contrast due to the liquid-solid transition in the islands allows the mapping of absolute temperature, as above or below the transition temperature, over the entire field-of-view. Experiments demonstrate nanoscale (<100 nm) resolution and video-rate (>30 thermal-images per second) speed, supported by combined electrical and thermal modeling. This provides a generic and adaptable platform for nanoscale thermal characterization independent of strong probe coupling and optical effects.

    View details for DOI 10.1021/nl0729375

    View details for Web of Science ID 000253166200038

    View details for PubMedID 18229968

  • Unexpected features of branched flow through high-mobility two-dimensional electron gases NATURE PHYSICS Jura, M. P., Topinka, M. A., Urban, L., Yazdani, A., Shtrikman, H., Pfeiffer, L. N., West, K. W., Goldhaber-Gordon, D. 2007; 3 (12): 841-845

    View details for DOI 10.1038/nphys756

    View details for Web of Science ID 000251456900018

  • Magnetic field dependence of the spin-1/2 and spin-1 Kondo effects in a quantum dot PHYSICAL REVIEW B Quay, C. H., Cumings, J., Gamble, S. J., de Picciotto, R., Kataura, H., Goldhaber-Gordon, D. 2007; 76 (24)
  • Transport properties of carbon nanotube C-60 peapods PHYSICAL REVIEW B Quay, C. H., Cumings, J., Gamble, S. J., Yazdani, A., Kataura, H., Goldhaber-Gordon, D. 2007; 76 (7)
  • Transport measurements across a tunable potential barrier in graphene PHYSICAL REVIEW LETTERS Huard, B., Sulpizio, J. A., Stander, N., Todd, K., Yang, B., Goldhaber-Gordon, D. 2007; 98 (23)

    Abstract

    The peculiar nature of electron scattering in graphene is among many exciting theoretical predictions for the physical properties of this material. To investigate electron scattering properties in a graphene plane, we have created a gate-tunable potential barrier within a single-layer graphene sheet. We report measurements of electrical transport across this structure as the tunable barrier potential is swept through a range of heights. When the barrier is sufficiently strong to form a bipolar junction (n-p-n or p-n-p) within the graphene sheet, the resistance across the barrier sharply increases. We compare these results to predictions for both diffusive and ballistic transport, as the barrier rises on a length scale comparable to the mean free path. Finally, we show how a magnetic field modifies transport across the barrier.

    View details for DOI 10.1103/PhysRevLett.98.236803

    View details for Web of Science ID 000247107200041

    View details for PubMedID 17677928

  • Charge rearrangement and screening in a quantum point contact PHYSICAL REVIEW LETTERS Luescher, S., Moore, L. S., Rejec, T., Meir, Y., Shtrikman, H., Goldhaber-Gordon, D. 2007; 98 (19)

    Abstract

    Compressibility measurements are performed on a quantum point contact (QPC). Screening due to mobile charges in the QPC is measured quantitatively, using a second point contact. These measurements are performed from pinch-off through the opening of the first few modes in the QPC. While the measured signal closely matches a Thomas-Fermi-Poisson prediction, deviations from the classical behavior are apparent near the openings of the different modes. Density functional calculations attribute the deviations to a combination of a diverging density of states at the opening of each one-dimensional mode and exchange interaction, which is strongest for the first mode.

    View details for DOI 10.1103/PhysRevLett.98.196805

    View details for Web of Science ID 000246413200043

    View details for PubMedID 17677648

  • Magnetic lattice surprise NATURE PHYSICS Moore, L. S., Goldhaber-Gordon, D. 2007; 3 (5): 295-296

    View details for DOI 10.1038/nphys610

    View details for Web of Science ID 000246738300006

  • Observation of the two-channel Kondo effect NATURE Potok, R. M., Rau, I. G., Shtrikman, H., Oreg, Y., Goldhaber-Gordon, D. 2007; 446 (7132): 167-171

    Abstract

    Some of the most intriguing problems in solid-state physics arise when the motion of one electron dramatically affects the motion of surrounding electrons. Traditionally, such highly correlated electron systems have been studied mainly in materials with complex transition metal chemistry. Over the past decade, researchers have learned to confine one or a few electrons within a nanometre-scale semiconductor 'artificial atom', and to understand and control this simple system in detail(3). Here we combine artificial atoms to create a highly correlated electron system within a nano-engineered semiconductor structure. We tune the system in situ through a quantum phase transition between two distinct states, each a version of the Kondo state, in which a bound electron interacts with surrounding mobile electrons. The boundary between these competing Kondo states is a quantum critical point-namely, the exotic and previously elusive two-channel Kondo state, in which electrons in two reservoirs are entangled through their interaction with a single localized spin.

    View details for DOI 10.1038/nature05556

    View details for Web of Science ID 000244718100036

    View details for PubMedID 17344849

  • Nanofabrication of top-gated carbon nanotube-based transistors: Probing electron-electron interactions in one-dimensional systems JOURNAL OF MATERIALS RESEARCH Sulpizio, J. A., Bandic, Z. Z., Goldhaber-Gordon, D. 2006; 21 (11): 2916-2921
  • Single-electron transistors in GaN/AlGaN heterostructures APPLIED PHYSICS LETTERS Chou, H. T., Goldhaber-Gordon, D., Schmult, S., Manfra, M. J., Sergent, A. M., Molnar, R. J. 2006; 89 (3)

    View details for DOI 10.1063/1.2226454

    View details for Web of Science ID 000239174100087

  • Greetings from three generations of Goldhabers to Academician Ginzburg, on the occasion of your 90th birthday JOURNAL OF SUPERCONDUCTIVITY AND NOVEL MAGNETISM Goldhaber, F., Goldhaber, M., Goldhaber-Gordon, D. 2006; 19 (3-5): 467-467
  • Quantum transport in high mobility AlGaN/GaN 2DEGs and nanostructures 6th International Conference on Nitride Semiconductors (ICNS-6) Schmult, S., Manfra, M. J., Sergent, A. M., Punnoose, A., Chou, H. T., Goldhaber-Gordon, D., Molnar, R. J. WILEY-V C H VERLAG GMBH. 2006: 1706–12
  • Tunable anomalous Hall effect in a nonferromagnetic system PHYSICAL REVIEW LETTERS Cumings, J., Moore, L. S., Chou, H. T., Ku, K. C., Xiang, G., Crooker, S. A., Samarth, N., Goldhaber-Gordon, D. 2006; 96 (19)

    Abstract

    We measure the low-field Hall resistivity of a magnetically doped two-dimensional electron gas as a function of temperature and electrically gated carrier density. Comparing these results with the carrier density extracted from Shubnikov-de Haas oscillations reveals an excess Hall resistivity that increases with decreasing temperature. This excess Hall resistivity qualitatively tracks the paramagnetic polarization of the sample, in analogy to the ferromagnetic anomalous Hall effect. The data are consistent with skew scattering of carriers by disorder near the crossover to localization.

    View details for DOI 10.1103/PhysRevLett.96.196404

    View details for Web of Science ID 000237683600032

    View details for PubMedID 16803118

  • Conductance fluctuations and partially broken spin symmetries in quantum dots PHYSICAL REVIEW B Zumbuhl, D. M., MILLER, J. B., Marcus, C. M., Goldhaber-Gordon, D., Harris, J. S., Campman, K., Gossard, A. C. 2005; 72 (8)
  • Electron microscopy of the operation of nanoscale devices. Microscopy and microanalysis Cummings, J., Goldhaber-Gordon, D., Zettl, A., McCartney, M. R., Spence, J. C. 2005; 11: 1504-1505

    Abstract

    Extended abstract of a paper presented at Microscopy and Microanalysis 2005 in Honolulu, Hawaii, USA, July 31--August 4, 2005.

    View details for DOI 10.1017/S1431927605510444

    View details for PubMedID 24017620

  • Nanotechnology - New spin on correlated electrons NATURE Potok, R. M., Goldhaber-Gordon, D. 2005; 434 (7032): 451-452

    View details for DOI 10.1038/434451a

    View details for Web of Science ID 000227836000027

    View details for PubMedID 15791241

  • Schrodinger's mousetrap - Part 6: A cryptic response. NATURE Goldhaber-Gordon, I., Goldhaber-Gordon, D. 2005; 433 (7028): 805-805

    View details for DOI 10.1038/433805a

    View details for Web of Science ID 000227174600021

  • Schrödinger's mousetrap. Part 6. Nature Goldhaber-Gordon, I., Goldhaber-Gordon, D. 2005; 433 (7028): 805-?

    View details for PubMedID 15729319

  • High-quality quantum point contacts in GaN/AlGaN heterostructures APPLIED PHYSICS LETTERS Chou, H. T., Luscher, S., Goldhaber-Gordon, D., Manfra, M. J., Sergent, A. M., West, K. W., Molnar, R. J. 2005; 86 (7)

    View details for DOI 10.1063/1.1862339

    View details for Web of Science ID 000227439400082

  • Electron Microscopy of the operation of nanoscale devices Symposium on Electron Microscopy of Molecular and Atom-Scale Mechanical Behavior, Chemistry and Structure held at the 2004 MRS Fall Meeting Cumings, J., Goldhaber-Gordon, D., Zettl, A., McCartney, M. R., Spence, J. C. MATERIALS RESEARCH SOCIETY. 2005: 165–176
  • Measurements of Kondo and spin splitting in single-electron transistors PHYSICAL REVIEW LETTERS Kogan, A., Amasha, S., Goldhaber-Gordon, D., Granger, G., Kastner, M. A., Shtrikman, H. 2004; 93 (16)

    Abstract

    We measure the spin splitting in a magnetic field B of localized states in single-electron transistors using a new method, inelastic spin-flip cotunneling. Because it involves only internal excitations, this technique gives the most precise value of the Zeeman energy Delta=/g/mu(B)B. In the same devices we also measure the splitting with B of the Kondo peak in differential conductance. The Kondo splitting appears only above a threshold field as predicted by theory. However, the magnitude of the Kondo splitting at high fields exceeds 2/g/mu(B)B in disagreement with theory.

    View details for DOI 10.1103/PhysRevLett.93.166602

    View details for Web of Science ID 000224533300062

    View details for PubMedID 15525018

  • Two-channel Kondo effect in a modified single electron transistor NATO Advanced Research Workshop on Molecular Nanowires and Other Quantum Objects Oreg, Y., Goldhaber-Gordon, D. SPRINGER. 2004: 67–76
  • Kondo effect and spin filtering in triangular artificial atoms SOLID STATE COMMUNICATIONS Zarand, G., Brataas, A., Goldhaber-Gordon, D. 2003; 126 (8): 463-466
  • Two-channel Kondo effect in a modified single electron transistor PHYSICAL REVIEW LETTERS Oreg, Y., Goldhaber-Gordon, D. 2003; 90 (13)

    Abstract

    We suggest a simple system of two electron droplets which should display two-channel Kondo behavior at experimentally accessible temperatures. Stabilization of the two-channel Kondo fixed point requires fine control of the electrochemical potential in each droplet, which can be achieved by adjusting voltages on nearby gate electrodes. We study the conditions for obtaining this type of two-channel Kondo behavior, discuss the experimentally observable consequences, and explore the generalization to the multichannel Kondo case.

    View details for DOI 10.1103/PhysRevLett.90.136602

    View details for Web of Science ID 000182032600045

    View details for PubMedID 12689314

  • Singlet-triplet transition in a single-electron transistor at zero magnetic field PHYSICAL REVIEW B Kogan, A., Granger, G., Kastner, M. A., Goldhaber-Gordon, D., Shtrikman, H. 2003; 67 (11)
  • Gate-controlled spin-orbit quantum interference effects in lateral transport PHYSICAL REVIEW LETTERS MILLER, J. B., Zumbuhl, D. M., Marcus, C. M., Lyanda-Geller, Y. B., Goldhaber-Gordon, D., Campman, K., Gossard, A. C. 2003; 90 (7)

    Abstract

    In situ control of spin-orbit coupling in coherent transport using a clean GaAs/AlGaAs two-dimensional electron gas is realized, leading to a gate-tunable crossover from weak localization to antilocalization. The necessary theory of 2D magnetotransport in the presence of spin-orbit coupling beyond the diffusive approximation is developed and used to analyze experimental data. With this theory the Rashba contribution and linear and cubic Dresselhaus contributions to spin-orbit coupling are separately estimated, allowing the angular dependence of spin-orbit precession to be extracted at various gate voltages.

    View details for DOI 10.1103/PhysRevLett.90.076807

    View details for Web of Science ID 000181090800043

    View details for PubMedID 12633263

  • Low-temperature fate of the 0.7 structure in a point contact: A Kondo-like correlated state in an open system PHYSICAL REVIEW LETTERS Cronenwett, S. M., Lynch, H. J., Goldhaber-Gordon, D., Kouwenhoven, L. P., Marcus, C. M., Hirose, K., Wingreen, N. S., Umansky, V. 2002; 88 (22)

    Abstract

    Besides the usual conductance plateaus at multiples of 2e(2)/h, quantum point contacts typically show an extra plateau at approximately 0.7(2e(2)/h), believed to arise from electron-electron interactions that prohibit the two spin channels from being simultaneously occupied. We present evidence that the disappearance of the 0.7 structure at very low temperature signals the formation of a Kondo-like correlated spin state. Evidence includes a zero-bias conductance peak that splits in a parallel field, scaling of conductance to a modified Kondo form, and consistency between peak width and the Kondo temperature.

    View details for DOI 10.1103/PhysRevLett.88.226805

    View details for Web of Science ID 000175709100037

    View details for PubMedID 12059445

  • Temperature dependence of Fano line shapes in a weakly coupled single-electron transistor PHYSICAL REVIEW B Zacharia, I. G., Goldhaber-Gordon, D., Granger, G., Kastner, M. A., Khavin, Y. B., Shtrikman, H., Mahalu, D., Meirav, U. 2001; 64 (15)
  • Molecular electronics - Momentous period for nanotubes NATURE Goldhaber-Gordon, D., Goldhaber-Gordon, I. 2001; 412 (6847): 594-?

    View details for Web of Science ID 000170318000023

    View details for PubMedID 11493901

  • Coulomb-blockade spectroscopy on a small quantum dot in a parallel magnetic field APPLIED PHYSICS LETTERS Duncan, D. S., Goldhaber-Gordon, D., Westervelt, R. M., Maranowski, K. D., Gossard, A. C. 2000; 77 (14): 2183-2185
  • Fano resonances in electronic transport through a single-electron transistor PHYSICAL REVIEW B Gores, J., Goldhaber-Gordon, D., Heemeyer, S., Kastner, M. A., Shtrikman, H., Mahalu, D., Meirav, U. 2000; 62 (3): 2188-2194
  • Suppression of the Kondo effect in a quantum dot by microwave radiation International Conference on Electron Transport in Mesoscopic Systems (ETMS '99) Elzerman, J. M., De Franceschi, S., Goldhaber-Gordon, D., van der Wiel, W. G., Kouwenhoven, L. P. SPRINGER/PLENUM PUBLISHERS. 2000: 375–89
  • From the Kondo regime to the mixed-valence regime in a single-electron transistor PHYSICAL REVIEW LETTERS Goldhaber-Gordon, D., Gores, J., Kastner, M. A., Shtrikman, H., Mahalu, D., Meirav, U. 1998; 81 (23): 5225-5228
  • Magnetic-field dependence of the level spacing of a small electron droplet PHYSICAL REVIEW B Klein, O., Goldhaber-Gordon, D., Chamon, C. D., Kastner, M. A. 1996; 53 (8): R4221-R4224
  • Phase transitions in artificial atoms NATO Advanced Study Institute on Quantum Transport in Semiconductor Submicron Structures Klein, O., Chamon, C. D., GoldhaberGordon, D., Kastner, M. A., Wen, X. G. SPRINGER. 1996: 239–249