Direct determination of resonance phase shifts of soft x-ray diffraction in thin films by momentum-transfer-sensitive three-wave interference

Abstract

A method for direct determination of resonance phase shifts in a (001) CdTe/InSb thin-film system is developed using soft x-ray three-wave resonance diffraction. At the (002) Bragg peaks of CdTe and InSb, two inversion-symmetry related three-wave diffractions are systematically identified according to crystal symmetry and the resonance phase shifts versus photon energies are measured without turning the thin film upside down. The momentum-transfer selectivity at (002) reflections facilitates the quantitative determination of the phase shifts near the $\text{Cd}\text{ }{L}_{3}$, $\text{Te}\text{ }{L}_{3}$, and $\text{Sb}\text{ }{L}_{2}$ edges.