Polarization Dependence of Two-Photon Absorption in Solids

Abstract

The polarization dependence of the rate of two-photon absorption has been calculated for all 32 crystallographic point groups. The method used by Inoue and Toyozawa to compute the polarization dependence of transitions from a ${\Gamma }^1$ (identity representation) ground state to an excited state of symmetry ${\Gamma }^{\alpha }$ (any single-valued representation) is extended to include all allowed two-photon transitions between pairs of states, each transforming according to any representation of the point group, including the double-valued representations. The results, presented in tabular form, are applicable to the analysis of transitions at point defects, and of band-to-band and exciton transitions at the center of the Brillouin zone.