title: Three-photon absorption in direct-gap crystals.
abstract: Third-order time-dependent perturbation theory, utilizing parabolic and nonparabolic energy bands and calculated (from band structure) higher bands as intermediate levels, and a Keldysh first-order model are used to calculate three-photon-absorption coefficients of several direct-gap crystals. Third-order perturbation results for CdS at 1.06 microm agree well with the experimental data.
authors.forename: S S
authors.initials: SS
authors.lastname: Mitra
authors.forename: N H
authors.initials: NH
authors.lastname: Judell
authors.forename: A
authors.initials: A
authors.lastname: Vaidyanathan
authors.forename: A H
authors.initials: AH
authors.lastname: Guenther