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arXiv · 2406.01962

Theory of resonant x-ray scattering with ultrafast intense pulses

Akilesh Venkatesh·Phay J. Ho
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Abstract

We present a time-dependent Schr\"odinger equation (TDSE) approach within a non-relativistic quantum electrodynamics (QED) framework to investigate resonant x-ray scattering under intense x-ray pulses. This method enables us to explore how coherent x-ray electron dynamics affect scattering signals from Ne$^+$. We account for both resonant fluorescence and elastic scattering channels, while also considering competing photoionization and inner-shell decay processes. By computing the angular distribution and energy spectrum of scattered photons, we uncover the interference effects between elastic scattering and resonant fluorescence pathways. Notably, our results reveal a small asymmetry in the energy spectrum as a result of this interference. We discuss the experimental potential for detecting signatures of interference. Our findings demonstrate that the x-ray Rabi dynamics can be used to control scattering responses and offer new insights into interference mechanisms and scattering efficiency in high-intensity x-ray regimes.

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Akilesh Venkatesh, Phay J. Ho. 2024-06-04. Theory of resonant x-ray scattering with ultrafast intense pulses. https://arxiv.org/abs/2406.01962

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