Speaker
Description
Coherent diffractive imaging of individual nanoparticles at FELs faces fundamental constraints due to rapid, dose-induced sample bleaching. This talk presents the first X-ray diffraction imaging experiments on individual nanoparticles utilizing intense, sub-femtosecond (sub-fs) pulses. At extreme peak power densities up to 10^20 W/cm², our data indicates that sub-fs exposures unlock novel regimes for manipulating the X-ray refractive index. Our data suggests that sub-fs pulses effectively mitigate and reversing transient radiation damage, and improve the quality of diffraction images. Furthermore, we demonstrate that the fluorescence emission excited during this ultra-short window encodes 3D structural data, accessible within a single exposure.
These findings demonstrate the untaped potential of sub-fs X-ray pulses for high-resolution, element-specific diffraction imaging. This approach opens a viable pathway to capture transient, non-equilibrium states of matter and resolve structural dynamics in systems like active catalytic reactions in real time.
Kuschel, Stephan, et al. "Non-linear enhancement of ultrafast X-ray diffraction through transient resonances." Nature Communications 16.1 (2025): 847.
Ulmer, Anatoli, et al. "Nonlinear reversal of photo-excitation on the attosecond time scale”, accepted at Nature Communications (2026)
| Scientific Topics | Imaging |
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