All Publications

  • Ultrafast x-ray detection of low-spin iron in molten silicate under deep planetary interior conditions. Science advances Shim, S. H., Ko, B., Sokaras, D., Nagler, B., Lee, H. J., Galtier, E., Glenzer, S., Granados, E., Vinci, T., Fiquet, G., Dolinschi, J., Tappan, J., Kulka, B., Mao, W. L., Morard, G., Ravasio, A., Gleason, A., Alonso-Mori, R. 2023; 9 (42): eadi6153


    The spin state of Fe can alter the key physical properties of silicate melts, affecting the early differentiation and the dynamic stability of the melts in the deep rocky planets. The low-spin state of Fe can increase the affinity of Fe for the melt over the solid phases and the electrical conductivity of melt at high pressures. However, the spin state of Fe has never been measured in dense silicate melts due to experimental challenges. We report detection of dominantly low-spin Fe in dynamically compressed olivine melt at 150 to 256 gigapascals and 3000 to 6000 kelvin using laser-driven shock wave compression combined with femtosecond x-ray diffraction and x-ray emission spectroscopy using an x-ray free electron laser. The observation of dominantly low-spin Fe supports gravitationally stable melt in the deep mantle and generation of a dynamo from the silicate melt portion of rocky planets.

    View details for DOI 10.1126/sciadv.adi6153

    View details for PubMedID 37862409

  • Simultaneous bright- and dark-field X-ray microscopy at X-ray free electron lasers. Scientific reports Dresselhaus-Marais, L. E., Kozioziemski, B., Holstad, T. S., Ræder, T. M., Seaberg, M., Nam, D., Kim, S., Breckling, S., Choi, S., Chollet, M., Cook, P. K., Folsom, E., Galtier, E., Gonzalez, A., Gorkhover, T., Guillet, S., Haldrup, K., Howard, M., Katagiri, K., Kim, S., Kim, S., Kim, S., Kim, H., Knudsen, E. B., Kuschel, S., Lee, H. J., Lin, C., McWilliams, R. S., Nagler, B., Nielsen, M. M., Ozaki, N., Pal, D., Pablo Pedro, R., Saunders, A. M., Schoofs, F., Sekine, T., Simons, H., van Driel, T., Wang, B., Yang, W., Yildirim, C., Poulsen, H. F., Eggert, J. H. 2023; 13 (1): 17573


    The structures, strain fields, and defect distributions in solid materials underlie the mechanical and physical properties across numerous applications. Many modern microstructural microscopy tools characterize crystal grains, domains and defects required to map lattice distortions or deformation, but are limited to studies of the (near) surface. Generally speaking, such tools cannot probe the structural dynamics in a way that is representative of bulk behavior. Synchrotron X-ray diffraction based imaging has long mapped the deeply embedded structural elements, and with enhanced resolution, dark field X-ray microscopy (DFXM) can now map those features with the requisite nm-resolution. However, these techniques still suffer from the required integration times due to limitations from the source and optics. This work extends DFXM to X-ray free electron lasers, showing how the [Formula: see text] photons per pulse available at these sources offer structural characterization down to 100 fs resolution (orders of magnitude faster than current synchrotron images). We introduce the XFEL DFXM setup with simultaneous bright field microscopy to probe density changes within the same volume. This work presents a comprehensive guide to the multi-modal ultrafast high-resolution X-ray microscope that we constructed and tested at two XFELs, and shows initial data demonstrating two timing strategies to study associated reversible or irreversible lattice dynamics.

    View details for DOI 10.1038/s41598-023-35526-5

    View details for PubMedID 37845245

    View details for PubMedCentralID 8279502

  • Probing shock dynamics inside micro-wire targets after high-intensity laser irradiation using small angle x-ray scattering of a free-electron laser NEW JOURNAL OF PHYSICS Kluge, T., Bussmann, M., Galtier, E., Glenzer, S., Grenzer, J., Gutt, C., Hartley, N. J., Huang, L., Garcia, A., Lee, H., Mcbride, E. E., Metzkes-Ng, J., Nakatsutsumi, M., Nam, I., Pelka, A., Prencipe, I., Randolph, L., Rehwald, M., Roedel, C., Roedel, M., Toncian, T., Yang, L., Zeil, K., Schramm, U., Cowan, T. E. 2023; 25 (10)
  • Multi-frame, ultrafast, x-ray microscope for imaging shockwave dynamics. Optics express Hodge, D. S., Leong, A. F., Pandolfi, S., Kurzer-Ogul, K., Montgomery, D. S., Aluie, H., Bolme, C., Carver, T., Cunningham, E., Curry, C. B., Dayton, M., Decker, F., Galtier, E., Hart, P., Khaghani, D., Ja Lee, H., Li, K., Liu, Y., Ramos, K., Shang, J., Vetter, S., Nagler, B., Sandberg, R. L., Gleason, A. E. 2022; 30 (21): 38405-38422


    Inertial confinement fusion (ICF) holds increasing promise as a potential source of abundant, clean energy, but has been impeded by defects such as micro-voids in the ablator layer of the fuel capsules. It is critical to understand how these micro-voids interact with the laser-driven shock waves that compress the fuel pellet. At the Matter in Extreme Conditions (MEC) instrument at the Linac Coherent Light Source (LCLS), we utilized an x-ray pulse train with ns separation, an x-ray microscope, and an ultrafast x-ray imaging (UXI) detector to image shock wave interactions with micro-voids. To minimize the high- and low-frequency variations of the captured images, we incorporated principal component analysis (PCA) and image alignment for flat-field correction. After applying these techniques we generated phase and attenuation maps from a 2D hydrodynamic radiation code (xRAGE), which were used to simulate XPCI images that we qualitatively compare with experimental images, providing a one-to-one comparison for benchmarking material performance. Moreover, we implement a transport-of-intensity (TIE) based method to obtain the average projected mass density (areal density) of our experimental images, yielding insight into how defect-bearing ablator materials alter microstructural feature evolution, material compression, and shock wave propagation on ICF-relevant time scales.

    View details for DOI 10.1364/OE.472275

    View details for PubMedID 36258406

  • Novel fabrication tools for dynamic compression targets with engineered voids using photolithography methods. The Review of scientific instruments Pandolfi, S., Carver, T., Hodge, D., Leong, A. F., Kurzer-Ogul, K., Hart, P., Galtier, E., Khaghani, D., Cunningham, E., Nagler, B., Lee, H. J., Bolme, C., Ramos, K., Li, K., Liu, Y., Sakdinawat, A., Marchesini, S., Kozlowski, P. M., Curry, C. B., Decker, F. J., Vetter, S., Shang, J., Aluie, H., Dayton, M., Montgomery, D. S., Sandberg, R. L., Gleason, A. E. 2022; 93 (10): 103502


    Mesoscale imperfections, such as pores and voids, can strongly modify the properties and the mechanical response of materials under extreme conditions. Tracking the material response and microstructure evolution during void collapse is crucial for understanding its performance. In particular, imperfections in the ablator materials, such as voids, can limit the efficiency of the fusion reaction and ultimately hinder ignition. To characterize how voids influence the response of materials during dynamic loading and seed hydrodynamic instabilities, we have developed a tailored fabrication procedure for designer targets with voids at specific locations. Our procedure uses SU-8 as a proxy for the ablator materials and hollow silica microspheres as a proxy for voids and pores. By using photolithography to design the targets' geometry, we demonstrate precise and highly reproducible placement of a single void within the sample, which is key for a detailed understanding of its behavior under shock compression. This fabrication technique will benefit high-repetition rate experiments at x-ray and laser facilities. Insight from shock compression experiments will provide benchmarks for the next generation of microphysics modeling.

    View details for DOI 10.1063/5.0107542

    View details for PubMedID 36319339

  • Novel fabrication tools for dynamic compression targets with engineered voids using photolithography methods REVIEW OF SCIENTIFIC INSTRUMENTS Pandolfi, S., Carver, T., Hodge, D., Leong, A. T., Kurzer-Ogul, K., Hart, P., Galtier, E., Khaghani, D., Cunningham, E., Nagler, B., Lee, H., Bolme, C., Ramos, K., Li, K., Liu, Y., Sakdinawat, A., Marchesini, S., Kozlowski, P. M., Curry, C. B., Decker, F., Vetter, S., Shang, J., Aluie, H., Dayton, M., Montgomery, D. S., Sandberg, R. L., Gleason, A. E. 2022; 93 (10)

    View details for DOI 10.1063/5.0107542

    View details for Web of Science ID 000869134800001

  • Diamond formation kinetics in shock-compressed C─H─O samples recorded by small-angle x-ray scattering and x-ray diffraction. Science advances He, Z., Rodel, M., Lutgert, J., Bergermann, A., Bethkenhagen, M., Chekrygina, D., Cowan, T. E., Descamps, A., French, M., Galtier, E., Gleason, A. E., Glenn, G. D., Glenzer, S. H., Inubushi, Y., Hartley, N. J., Hernandez, J., Heuser, B., Humphries, O. S., Kamimura, N., Katagiri, K., Khaghani, D., Lee, H. J., McBride, E. E., Miyanishi, K., Nagler, B., Ofori-Okai, B., Ozaki, N., Pandolfi, S., Qu, C., Ranjan, D., Redmer, R., Schoenwaelder, C., Schuster, A. K., Stevenson, M. G., Sueda, K., Togashi, T., Vinci, T., Voigt, K., Vorberger, J., Yabashi, M., Yabuuchi, T., Zinta, L. M., Ravasio, A., Kraus, D. 2022; 8 (35): eabo0617


    Extreme conditions inside ice giants such as Uranus and Neptune can result in peculiar chemistry and structural transitions, e.g., the precipitation of diamonds or superionic water, as so far experimentally observed only for pure C─H and H2O systems, respectively. Here, we investigate a stoichiometric mixture of C and H2O by shock-compressing polyethylene terephthalate (PET) plastics and performing in situ x-ray probing. We observe diamond formation at pressures between 72 ± 7 and 125 ± 13 GPa at temperatures ranging from ~3500 to ~6000 K. Combining x-ray diffraction and small-angle x-ray scattering, we access the kinetics of this exotic reaction. The observed demixing of C and H2O suggests that diamond precipitation inside the ice giants is enhanced by oxygen, which can lead to isolated water and thus the formation of superionic structures relevant to the planets' magnetic fields. Moreover, our measurements indicate a way of producing nanodiamonds by simple laser-driven shock compression of cheap PET plastics.

    View details for DOI 10.1126/sciadv.abo0617

    View details for PubMedID 36054354

  • Femtosecond Visualization of hcp-Iron Strength and Plasticity under Shock Compression. Physical review letters Merkel, S., Hok, S., Bolme, C., Rittman, D., Ramos, K. J., Morrow, B., Lee, H. J., Nagler, B., Galtier, E., Granados, E., Hashim, A., Mao, W. L., Gleason, A. E. 2021; 127 (20): 205501


    Iron is a key constituent of planets and an important technological material. Here, we combine insitu ultrafast x-ray diffraction with laser-induced shock compression experiments on Fe up to 187(10)GPa and 4070(285)K at 10^{8}s^{-1} in strain rate to study the plasticity of hexagonal-close-packed (hcp)-Fe under extreme loading states. {101[over ]2} deformation twinning controls the polycrystalline Fe microstructures and occurs within 1ns, highlighting the fundamental role of twinning in hcp polycrystals deformation at high strain rates. The measured deviatoric stress initially increases to a significant elastic overshoot before the onset of flow, attributed to a slower defect nucleation and mobility. The initial yield strength of materials deformed at high strain rates is thus several times larger than their longer-term flow strength. These observations illustrate how time-resolved ultrafast studies can reveal distinctive plastic behavior in materials under extreme environments.

    View details for DOI 10.1103/PhysRevLett.127.205501

    View details for PubMedID 34860050

  • Ultrafast X-ray Diffraction Study of a Shock-Compressed Iron Meteorite above 100 GPa MINERALS Tecklenburg, S., Colina-Ruiz, R., Hok, S., Bolme, C., Galtier, E., Granados, E., Hashim, A., Lee, H., Merkel, S., Morrow, B., Nagler, B., Ramos, K., Rittman, D., Walroth, R., Mao, W. L., Gleason, A. E. 2021; 11 (6)
  • Ronchi shearing interferometry for wavefronts with circular symmetry JOURNAL OF SYNCHROTRON RADIATION Nagler, B., Galtier, E. C., Brown, S. B., Heimann, P., Dyer, G., Lee, H. 2020; 27: 1461–69


    Ronchi testing of a focused electromagnetic wave has in the last few years been used extensively at X-ray free-electron laser (FEL) facilities to qualitatively evaluate the wavefront of the beam. It is a quick and straightforward test, is easy to interpret on the fly, and can be used to align phase plates that correct the focus of aberrated beams. In general, a single Ronchigram is not sufficient to gain complete quantitative knowledge of the wavefront. However the compound refractive lenses that are commonly used at X-ray FELs exhibit a strong circular symmetry in their aberration, and this can be exploited. Here, a simple algorithm that uses a single recorded Ronchigram to recover the full wavefront of a nano-focused beam, assuming circular symmetry, is presented, and applied to experimental measurements at the Matter in Extreme Conditions instrument at the Linac Coherent Light Source.

    View details for DOI 10.1107/S1600577520010735

    View details for Web of Science ID 000588645400001

    View details for PubMedID 33147170

  • In situ X-ray diffraction of silicate liquids and glasses under dynamic and static compression to megabar pressures. Proceedings of the National Academy of Sciences of the United States of America Morard, G. n., Hernandez, J. A., Guarguaglini, M. n., Bolis, R. n., Benuzzi-Mounaix, A. n., Vinci, T. n., Fiquet, G. n., Baron, M. A., Shim, S. H., Ko, B. n., Gleason, A. E., Mao, W. L., Alonso-Mori, R. n., Lee, H. J., Nagler, B. n., Galtier, E. n., Sokaras, D. n., Glenzer, S. H., Andrault, D. n., Garbarino, G. n., Mezouar, M. n., Schuster, A. K., Ravasio, A. n. 2020


    Properties of liquid silicates under high-pressure and high-temperature conditions are critical for modeling the dynamics and solidification mechanisms of the magma ocean in the early Earth, as well as for constraining entrainment of melts in the mantle and in the present-day core-mantle boundary. Here we present in situ structural measurements by X-ray diffraction of selected amorphous silicates compressed statically in diamond anvil cells (up to 157 GPa at room temperature) or dynamically by laser-generated shock compression (up to 130 GPa and 6,000 K along the MgSiO3 glass Hugoniot). The X-ray diffraction patterns of silicate glasses and liquids reveal similar characteristics over a wide pressure and temperature range. Beyond the increase in Si coordination observed at 20 GPa, we find no evidence for major structural changes occurring in the silicate melts studied up to pressures and temperatures exceeding Earth's core mantle boundary conditions. This result is supported by molecular dynamics calculations. Our findings reinforce the widely used assumption that the silicate glasses studies are appropriate structural analogs for understanding the atomic arrangement of silicate liquids at these high pressures.

    View details for DOI 10.1073/pnas.1920470117

    View details for PubMedID 32414927

  • Focal Spot and Wavefront Sensing of an X-Ray Free Electron laser using Ronchi shearing interferometry SCIENTIFIC REPORTS Nagler, B., Aquila, A., Boutet, S., Galtier, E. C., Hashim, A., Hunter, M. S., Liang, M., Sakdinawat, A. E., Schroer, C. G., Schropp, A., Seaberg, M. H., Seiboth, F., van Driel, T., Xing, Z., Liu, Y., Lee, H. 2017; 7: 13698


    The Linac Coherent Light Source (LCLS) is an X-ray source of unmatched brilliance, that is advancing many scientific fields at a rapid pace. The highest peak intensities that are routinely produced at LCLS take place at the Coherent X-ray Imaging (CXI) instrument, which can produce spotsize at the order of 100 nm, and such spotsizes and intensities are crucial for experiments ranging from coherent diffractive imaging, non-linear x-ray optics and high field physics, and single molecule imaging. Nevertheless, a full characterisation of this beam has up to now not been performed. In this paper we for the first time characterise this nanofocused beam in both phase and intensity using a Ronchi Shearing Interferometric technique. The method is fast, in-situ, uses a straightforward optimization algoritm, and is insensitive to spatial jitter.

    View details for DOI 10.1038/s41598-017-13710-8

    View details for Web of Science ID 000413357500064

    View details for PubMedID 29057938

    View details for PubMedCentralID PMC5651859

  • Shock drive capabilities of a 30-Joule laser at the matter in extreme conditions hutch of the Linac Coherent Light Source REVIEW OF SCIENTIFIC INSTRUMENTS Brown, S., Hashim, A., Gleason, A., Galtier, E., Nam, I., Xing, Z., Fry, A., MacKinnon, A., Nagler, B., Granados, E., Lee, H. 2017; 88 (10): 105113


    We measure the shock drive capabilities of a 30 J, nanosecond, 527 nm laser system at the matter in extreme conditions hutch of the Linac Coherent Light Source. Using a velocity interferometer system for any reflector, we ascertain the maximum instantaneous ablation pressure and characterize its dependence on a drive laser spot size, spatial profile, and temporal profile. We also examine the effects of these parameters on shock spatial and temporal uniformity. Our analysis shows the drive laser capable of generating instantaneous ablation pressures exceeding 160 GPa while maintaining a 1D shock profile. We find that slope pulses provide higher instantaneous ablation pressures than plateau pulses. Our results show instantaneous ablation pressures comparable to those measured at the Omega Laser Facility in Rochester, NY under similar optical drive parameters. Finally, we analyze how optical laser ablation pressures are compare with known scaling relations, accounting for variable laser wavelengths.

    View details for PubMedID 29092479

  • The phase-contrast imaging instrument at the matter in extreme conditions endstation at LCLS REVIEW OF SCIENTIFIC INSTRUMENTS Nagler, B., Schropp, A., Galtier, E. C., Arnold, B., Brown, S. B., Fry, A., Gleason, A., Granados, E., Hashim, A., Hastings, J. B., Samberg, D., Seiboth, F., Tavella, F., Xing, Z., Lee, H. J., Schroer, C. G. 2016; 87 (10)


    We describe the phase-contrast imaging instrument at the Matter in Extreme Conditions (MEC) endstation of the Linac Coherent Light Source. The instrument can image phenomena with a spatial resolution of a few hundreds of nanometers and at the same time reveal the atomic structure through X-ray diffraction, with a temporal resolution better than 100 fs. It was specifically designed for studies relevant to high-energy-density science and can monitor, e.g., shock fronts, phase transitions, or void collapses. This versatile instrument was commissioned last year and is now available to the MEC user community.

    View details for DOI 10.1063/1.4963906

    View details for Web of Science ID 000387661900033

    View details for PubMedID 27802688

  • Bent crystal spectrometer for both frequency and wavenumber resolved x-ray scattering at a seeded free-electron laser REVIEW OF SCIENTIFIC INSTRUMENTS Zastrau, U., Fletcher, L. B., Foerster, E., Galtier, E. C., Gamboa, E., Glenzer, S. H., Heimann, P., Marschner, H., Nagler, B., Schropp, A., Wehrhan, O., Lee, H. J. 2014; 85 (9)


    We present a cylindrically curved GaAs x-ray spectrometer with energy resolution ΔE/E = 1.1 × 10(-4) and wave-number resolution of Δk/k = 3 × 10(-3), allowing plasmon scattering at the resolution limits of the Linac Coherent Light Source (LCLS) x-ray free-electron laser. It spans scattering wavenumbers of 3.6 to 5.2/Å in 100 separate bins, with only 0.34% wavenumber blurring. The dispersion of 0.418 eV/13.5 μm agrees with predictions within 1.3%. The reflection homogeneity over the entire wavenumber range was measured and used to normalize the amplitude of scattering spectra. The proposed spectrometer is superior to a mosaic highly annealed pyrolytic graphite spectrometer when the energy resolution needs to be comparable to the LCLS seeded bandwidth of 1 eV and a significant range of wavenumbers must be covered in one exposure.

    View details for DOI 10.1063/1.4894821

    View details for Web of Science ID 000342910500007