Contribution List

13 out of 13 displayed
  1. Jonathan Lang (Argonne National Laboratory)
    5/6/26, 8:30 AM
  2. Ian Robinson (Brookhaven National Laboratory)
    5/6/26, 8:40 AM

    We performed ultrafast time-resolved diffraction experiments at the x-ray free-electron laser (XFEL) facility in
    Pohang, Korea to study 300 nm polycrystalline thin films of gold evaporated onto silicon nitride windows,
    melted by a Ti-sapphire laser pulse [1]. A clear splitting of the (111) powder ring was found at certain fluences
    after a time delay of 20-100 ps. From the evolution of the...

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  3. Peijun Guo (Yale)
    5/6/26, 9:05 AM

    Developing light-emitting semiconductors with high photoluminescence quantum yield (PLQY) is important for
    energy-efficient solid-state lighting applications. A subset of solution-processed metal halide perovskites has
    been shown to exhibit intrinsic, broadband white-light emission with high PLQY from 10% to 90%. The
    intrinsic white-light emission is attributed to self-trapped excitons...

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  4. Alfred Zong (Stanford University)
    5/6/26, 9:30 AM

    Photoexcitation by ultrashort laser pulses plays a crucial role in controlling reaction pathways, creating
    nonequilibrium material properties, and offering a microscopic view of complex dynamics at the molecular
    level. The photo-response following a laser pulse is, in general, non-identical between multiple exposures due to
    spatiotemporal fluctuations in a material or the stochastic nature...

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  5. Anne Marie March (Argonne National Laboratory)
    5/6/26, 10:15 AM

    We are using a multi-edge, time-resolved x-ray spectroscopy approach to investigate how the solvent
    environment controls reactivity in aqueous iron hexacyanide. This highly charged coordination complex
    ([Fe(CN)₆]⁴⁻) exhibits useful redox behavior ([Fe²⁺(CN)₆]⁴⁻ ⇌ [Fe³⁺(CN)₆]³⁻) alongside a minor ligand exchange
    reaction in which CN⁻ is released and replaced by water. We ask whether...

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  6. Mingda Li (Massachusetts Institute of Technology)
    5/6/26, 10:40 AM

    Defects and structural disorder govern materials functionality, yet their quantitative, non-destructive
    characterization remains a major challenge. For defect configuration, we introduce DefectNet, a foundation
    model that predicts the chemical identity and concentration of multiple coexisting substitutional point defects
    directly from phonon density-of-states spectra. Trained on over 16,000...

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  7. Xiaoyi Zhang
    5/6/26, 11:05 AM

    This brief presentation will highlight the Time-Resolved Research Group’s new and enhanced capabilities
    developed to leverage the APS Upgrade, including pump-probe multimodal imaging and diffraction, grazing-
    incidence scattering, pair distribution function measurements, and double-laser-pump TR-XAS. Delivered
    immediately before the 40-minute discussion period in the morning session, it is...

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  8. Philippe Piot
    5/6/26, 1:30 PM

    Argonne National Laboratory is exploring next-generation x-ray free-electron laser (XFEL) concepts to enable
    capabilities beyond existing facilities while complementing the Advanced Photon Source (APS) storage ring. In
    this early phase, the focus is on architectures that support multi-user operation and deliver versatile photon-
    pulse characteristics, including flexible temporal structure,...

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  9. Agostino Marinelli
    5/6/26, 1:50 PM

    X-ray free-electron lasers (XFELs) are the brightest sources of x-rays available, with a peak brightness that
    surpasses table-top harmonic sources and synchrotron radiation facilities by many orders of magnitude.
    A defining feature of XFELs is their inherent flexibility, which enables the control of the spectral, spatial, and
    temporal properties of the radiation and tailoring of the pulse...

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  10. Uwe Bergmann (University of Wisconsin, Madison)
    5/6/26, 2:15 PM

    We present our progress in exploring the phenomenon of stimulated x-ray emission spectroscopy (S-XES)
    based on inner-shell lasing at 6 – 8 keV as a new spectroscopy tool, and as a new source of ultrafast hard x-ray
    pulses. We first discuss the principle of S-XES, and the experimental methods required for generating and
    measuring it. We then discuss recent results for spectroscopy...

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  11. Thomas Wolf (SLAC National Laboratory & Stanford University)
    5/6/26, 3:20 PM

    X-ray free electron lasers (XFELs), with their unique source properties—including femtosecond and sub-
    femtosecond pulse durations, high peak brightness, and coherence—offer compelling opportunities for chemical
    research. These capabilities allow for the investigation of compounds undergoing photochemical reactions using
    site- and element-specific spectroscopy, and, in parallel, for...

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  12. Yue Cao (Argonne National Laboratory)
    5/6/26, 3:45 PM

    In this talk, I will discuss scientific opportunities at the proposed compact XFEL. These opportunities center
    around the ultrafast dynamics in quantum materials. These dynamics include changes in the electron
    wavefunction and density within atomic clusters or cages, as well as evolutions of charge and magnetic
    domains. In both cases, x-ray resonance and polarization will play a central...

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  13. Lois Pollack (Cornell University)
    5/6/26, 4:10 PM

    X-rays from XFEL sources have had enormous impact on structural biology both through crystallography and
    solution scattering. The new methods demonstrated at XFELs focus on measuring the structural dynamics of
    biological macromolecules; these motions enable life. The demonstration of serial femtosecond crystallography,
    where tens of thousands of small crystals are individually sampled by...

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