Coherent Stimulated X-ray Raman Spectroscopy; Attosecond Extension of RIXS

Abstract

Spontaneous and stimulated resonant inelastic X-ray Raman scattering signals are calculated using the Keldysh-Schwinger closed-time path loop and expressed as overlaps of Doorway and Window electron-hole wavepackets. These are recast in terms of the one-particle Green's functions and expansion coefficients of configuration interaction singles for valence excitations, which can be obtained from standard electronic structure codes. Calculation for many-body states of ground and core-excited system is avoided.