Nonlinear reversal of photoexcitation on the attosecond time scale improves ultrafast X-ray diffraction images

Ulmer, Anatoli [Universität Hamburg (Germany)] (ORCID:0000000178643063); Ho, Phay J. [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000152142180); Langbehn, Bruno [Technische Universität Berlin (Germany)] (ORCID:0000000232458169); Kuschel, Stephan [Universität Hamburg (Germany); Technical University Darmstadt (Germany)] (ORCID:000000015159525X); Hecht, Linos [ETH Zurich (Switzerland)] (ORCID:0000000333421218); Obaid, Razib [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)]; Dold, Simon [European XFEL, Schenefeld (Germany)] (ORCID:0000000153328251); Driver, Taran [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000237616883); Duris, Joseph [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000299301166); Lin, Ming-Fu [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000180862484); Cesar, David [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000336691854); Franz, Paris [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)]; Guo, Zhaoheng [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Stanford University, CA (United States)] (ORCID:0000000338738804); Hart, Philip A. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)]; Kamalov, Andrei [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)]; Larsen, Kirk A. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:000000023252260X); Li, Xiang [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000183384123); Meyer, Michael [European XFEL, Schenefeld (Germany)] (ORCID:0000000214446770); Nakahara, Kazutaka [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)]; Radloff, Robert G. [Universität Hamburg (Germany)]; Robles, River [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000271524675); Rönnebeck, Lara [Universität Hamburg (Germany)]; Sudar, Nick [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)]; Summers, Adam M. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000326944969); Young, Linda [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:000000022251039X); Walter, Peter [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000188391154); Cryan, James P. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000277760919); Bostedt, Christoph [PSI, Paul-Scherrer-Institute, Villigen (Switzerland); École Polytechnique Fédérale de Lausanne (EPFL), Lausanne (Switzerland)]; Rupp, Daniela [ETH Zurich (Switzerland)]; Marinelli, Agostino [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000272484652); Gorkhover, Tais [Universität Hamburg (Germany)] (ORCID:0009000188041186)

doi:10.1038/s41467-026-75969-8

DOE OSTI · 3392253

Nonlinear reversal of photoexcitation on the attosecond time scale improves ultrafast X-ray diffraction images

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Abstract

The complex refractive index of a material governs its light-matter interactions, with intense light fields enabling tailored nonlinear optical responses. In the X-ray regime, rapid photoionization limits the potential of nonlinear techniques by inducing irreversible electronic damage. Here we demonstrate that intense, sub-femtosecond X-ray pulses, shorter than typical Auger decay times, can partially reverse photoexcitation via stimulated emission near atomic resonances. By analyzing thousands of coherent diffraction patterns and ion spectra from neon nanoparticles exposed to sub-fs and 15-fs pulses, we observe enhanced X-ray diffraction alongside reduced energy absorption for sub-fs pulses. Theoretical modeling attributes this to dynamics akin to Rabi flopping that prolong the lifetime of resonant states and suppress electronic bleaching. These findings suggest that ultrashort, intense X-ray pulses enable active control of X-ray refractive index and damage pathways, opening avenues for improved high-resolution imaging and nonlinear spectroscopy in complex nanoscale systems.

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Ulmer, Anatoli [Universität Hamburg (Germany)] (ORCID:0000000178643063), Ho, Phay J. [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:0000000152142180), Langbehn, Bruno [Technische Universität Berlin (Germany)] (ORCID:0000000232458169), Kuschel, Stephan [Universität Hamburg (Germany); Technical University Darmstadt (Germany)] (ORCID:000000015159525X), Hecht, Linos [ETH Zurich (Switzerland)] (ORCID:0000000333421218), Obaid, Razib [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)], Dold, Simon [European XFEL, Schenefeld (Germany)] (ORCID:0000000153328251), Driver, Taran [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000237616883), Duris, Joseph [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000299301166), Lin, Ming-Fu [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000180862484), Cesar, David [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000336691854), Franz, Paris [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)], Guo, Zhaoheng [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Stanford University, CA (United States)] (ORCID:0000000338738804), Hart, Philip A. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)], Kamalov, Andrei [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)], Larsen, Kirk A. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:000000023252260X), Li, Xiang [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000183384123), Meyer, Michael [European XFEL, Schenefeld (Germany)] (ORCID:0000000214446770), Nakahara, Kazutaka [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)], Radloff, Robert G. [Universität Hamburg (Germany)], Robles, River [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000271524675), Rönnebeck, Lara [Universität Hamburg (Germany)], Sudar, Nick [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)], Summers, Adam M. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000326944969), Young, Linda [Argonne National Laboratory (ANL), Argonne, IL (United States)] (ORCID:000000022251039X), Walter, Peter [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000188391154), Cryan, James P. [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000277760919), Bostedt, Christoph [PSI, Paul-Scherrer-Institute, Villigen (Switzerland); École Polytechnique Fédérale de Lausanne (EPFL), Lausanne (Switzerland)], Rupp, Daniela [ETH Zurich (Switzerland)], Marinelli, Agostino [SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)] (ORCID:0000000272484652), Gorkhover, Tais [Universität Hamburg (Germany)] (ORCID:0009000188041186). 2026-07-28. Nonlinear reversal of photoexcitation on the attosecond time scale improves ultrafast X-ray diffraction images. https://doi.org/10.1038/s41467-026-75969-8

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