Kuschel Stephan, Ho Phay J, Al Haddad Andre, Zimmermann Felix F, Flueckiger Leonie, Ware Matthew R, Duris Joseph, MacArthur James P, Lutman Alberto, Lin Ming-Fu, Li Xiang, Nakahara Kazutaka, Aldrich Jeff W, Walter Peter, Young Linda, Bostedt Christoph, Marinelli Agostino, Gorkhover Tais
SLAC National Accelerator Laboratory, Stanford PULSE Institute, Menlo Park, CA, USA.
SLAC National Accelerator Laboratory, Menlo Park, CA, USA.
Nat Commun. 2025 Jan 20;16(1):847. doi: 10.1038/s41467-025-56046-y.
Diffraction-before-destruction imaging with ultrashort X-ray pulses can visualize non-equilibrium processes, such as chemical reactions, with sub-femtosecond precision in the native environment. Here, a nanospecimen diffracts a single X-ray flash before it disintegrates. The sample structure can be reconstructed from the coherent diffraction image (CDI). State-of-the-art X-ray snapshots lack high spatial resolution because of weak diffraction signal. Bleaching effects from photo-ionization significantly restrain image brightness scaling. We find that non-linear transient ion resonances can overcome this barrier if X-ray laser pulses are shorter than in most experiments. We compared snapshots from individual ≈ 100 nm Xe nanoparticles as a function of pulse duration and incoming X-ray fluence. Our experimental results and Monte Carlo simulations suggest that transient resonances can increase ionic scattering cross sections significantly beyond literature values. This provides a novel avenue towards substantial improvement of the spatial resolution in CDI in combination with sub-femtosecond temporal precision at the nanoscale.
利用超短X射线脉冲进行破坏前衍射成像能够在自然环境中以亚飞秒精度可视化非平衡过程，如化学反应。在此，一个纳米样本在解体前衍射单个X射线闪光。样本结构可从相干衍射图像（CDI）重建。由于衍射信号微弱，当前的X射线快照缺乏高空间分辨率。光电离产生的漂白效应显著限制了图像亮度缩放。我们发现，如果X射线激光脉冲比大多数实验中的更短，非线性瞬态离子共振可以克服这一障碍。我们比较了单个约100纳米氙纳米颗粒的快照，作为脉冲持续时间和入射X射线通量的函数。我们的实验结果和蒙特卡罗模拟表明，瞬态共振可以使离子散射截面显著增加，远超文献值。这为在纳米尺度上结合亚飞秒时间精度大幅提高CDI的空间分辨率提供了一条新途径。
