Attosecond Science at the Linac Coherent Light Source
POSTER
Abstract
We report the first results using isolated attosecond soft X-ray pulses from an X-ray free-electron laser (XFEL)\footnote{Duris, Li \textit{et al.}, Nat. Phot. \textbf{14}, 30 (2020)}. This new attosecond source produces peak powers on the gigawatt scale,and opens the door for a suite of X-ray spectroscopies probing few- to sub-femtosecond dynamics. High peak power pulses facilitate nonlinear spectroscopies such as attosecond X-ray pump/attosecond X-ray probe, and wave mixing. Moreover, the inherent tunability of an XFEL source allows the selective probing of different core-to-valence transitions at disparate atomic site in a molecule, providing an atomic site-specific probe of valence electron dynamics. We present single-shot attosecond pulse characterization, the preparation of a coherent electronic wavepacket \textit{via} stimulated X-ray Raman scattering, time-resolved photoemission studies of pre-edge~(resonant Auger) and post-edge~(direct) \textit{K}-shell ionization and two-color, two-pulse operation.
*This work was supported by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Chemical Sciences, Geosciences, and Biosciences Division. Use of the Linac Coherent Light Source (LCLS), SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515.