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PUBLICATIONS

Non-resonant Two-photon X-ray Absorption in Cu

Published

Author(s)

Joshua Kas, John Rehr, Joachim Stöhr, John Vinson

Abstract

We present a real-space Green's function theory and calculations of two-photon x-ray absorption (TPA). Our focus is on nonresonant K-shell TPA in metallic Cu, which has been observed experimentally at intense x-ray free electron laser (XFEL) sources. The theory is based on an independent particle Green's function treatment of the Kramers-Heisenberg equation and an approximation for the sum over nonresonant intermediate states in terms of a static quadrupole transition operator. XFEL effects are modeled by a partially depleted d band. This approach is shown to give results for K-shell TPA in quantitative agreement with XFEL experiment and with a Bethe-Salpeter equation approach. We also briefly discuss many-body corrections and TPA sum rules.
Citation
Physical Review B
Volume
112
Pub Type
Journals

Download Paper

https://doi.org/10.1103/t8cn-d9yy
Local Download
Spectroscopy and Condensed matter

Citation

Kas, J. , Rehr, J. , Stöhr, J. and Vinson, J. (2025), Non-resonant Two-photon X-ray Absorption in Cu, Physical Review B, [online], https://doi.org/10.1103/t8cn-d9yy, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=959610 (Accessed October 13, 2025)

Issues

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Created July 10, 2025, Updated July 11, 2025
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