Two-photon absorption using off-resonant excitation with ultrashort X-ray pulses

29th International Conference on Photonic, Electronic, and Atomic Collisions

Szlachetko, J.^1,2 ; Hoszowska, J.^3 ; Dousse, J.-Cl.^3 ; Patterson, B.^1 ; Abela, R.^1 ; Pajek, M.^2 ; Milne, C.J.^1

Paul Scherrer Institute, Villigen-PSI, Switzerland^1

Insitute of Physics, Jan Kochanowski University, Kielce, Poland^2

Department of Physics, University of Fribourg, Fribourg, Switzerland^3

关键词: High-energy resolution;    Linac Coherent Light Source;    Multiple crystals;    Off-resonant excitation;    Resonant x-ray emission spectroscopies;    Two photon absorption;    Ultrashort x-ray pulse;    Universal scaling;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/635/9/092147/pdf
DOI  :  10.1088/1742-6596/635/9/092147

来源: IOP

【 摘 要 】

High energy resolution off-resonant X-ray emission spectroscopy (HEROS) was applied to study one-photon (OPA) and two-photon absorption (TPA) processes in metallic copper generated by ultra-short hard X- ray FEL pulses from the Linac Coherent Light Source (LCLS). The OPA and TPA signals were measured using a multiple-crystal von Hamos diffraction spectrometer allowing observation of both the intermediate and final states in the TPA process. The universal scaling of TPA/OPA cross sections is discussed.