Polarization dependence of the two-photon absorption coefficient in crystals

Abstract

The theory of two-photon absorption with provision for exciton effects is built on the basis of general principles without using any model of electronic states of the crystal. Electron-phonon interaction is neglected. The splitting of exciton levels into levels of transverse and longitudinal excitons is taken into account. The polarization dependence of two-photon absorption coefficient of allowed two-photon dipole transitions from the ground state of crystal for all 32 crystallographic classes is calculated. The results obtained are compared with the experimental data available.