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arXiv · 2110.10197

Ghost-imaging-enhanced non-invasive spectral characterization of stochastic x-ray free-electron-laser pulses

Kai Li·Joakim Laksman·Tommaso Mazza·Gilles Doumy·Dimitris Koulentianos·Alessandra Picchiotti·Svitovar Serkez·Nina Rohringer·Markus Ilchen·Michael Meyer·Linda Young
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Abstract

High-intensity ultrashort X-ray free-electron laser (XFEL) pulses are revolutionizing the study of fundamental nonlinear x-ray matter interactions and coupled electronic and nuclear dynamics. To fully exploit the potential of this powerful tool for advanced x-ray spectroscopies, a noninvasive spectral characterization of incident stochastic XFEL pulses with high resolution is a key requirement. Here we present a methodology that combines high-acceptance angle-resolved photoelectron time-of-flight spectroscopy and ghost imaging to enhance the quality of spectral characterization of x-ray free-electron laser pulses. Implementation of this non-invasive high-resolution x-ray diagnostic can greatly benefit the ultrafast x-ray spectroscopy community by functioning as a transparent beamsplitter for applications such as transient absorption spectroscopy in averaging mode as well as covariance-based x-ray nonlinear spectroscopies in single-shot mode where the shot-to-shot fluctuations inherent to a self-amplified spontaneous emission (SASE) XFEL pulse are a powerful asset.

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Kai Li, Joakim Laksman, Tommaso Mazza, Gilles Doumy, Dimitris Koulentianos, Alessandra Picchiotti, Svitovar Serkez, Nina Rohringer, Markus Ilchen, Michael Meyer, Linda Young. 2021-10-19. Ghost-imaging-enhanced non-invasive spectral characterization of stochastic x-ray free-electron-laser pulses. https://arxiv.org/abs/2110.10197

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