Fig. 3: Model of nonlinear X-ray spectra.
From: Stimulated resonant inelastic X-ray scattering in a solid
Here, spont. stands for spontaneous, stim./stimul. stand for stimulated, redist. stands for redistribution, rel. stands for relative, NL stands for nonlinear and EF is the Fermi energy. a Model Co L3 spontaneous Resonant Inelastic X-ray Scattering (RIXS, gray), X-Ray Absorption Spectrum (XAS, black) and transmission (red) spectra, and three assumed non-linear contributions, stimulated RIXS (magenta), electron redistribution (green) and stimulated Resonant Elastic X-ray Scattering (REXS, blue). The sizes of the nonlinear contributions are referenced to the unit value of the XAS peak. b Assumed incident pulse reference distribution (dashed), which allows all three nonlinear channels to contribute to the sum shown in black. c Shifted pulse reference distribution (dashed) which eliminates the stimulated RIXS contribution. The remaining two add up the sum shown in black. d Change of the spontaneous transmission spectrum (red) taken from (a), to the total nonlinear transmission one (black) for a wide incident energy distribution. The black curve is the red curve plus the the sum of all three nonlinear contributions. Colored arrows indicate nonlinear transmission gain (up arrows) and loss (down arrows) caused by the respective nonlinear channels.
