Description:
<jats:title>Abstract</jats:title><jats:p>The two‐photon absorption coefficient in crystals is discussed for the case, where one or both exciting beams are circularly polarized. The procedure previously used for linearly polarized light is extended to include circularly polarized photons, and also in this case the absorption coefficient is factorized into dynamical factors containing matrix elements of the momentum operator, and into geometrical factors which depend on the polarization directions of the linearly polarized beams, and on the propagation vectors of the circularly polarized beams. Detailed tables of the geometrical factors are given in the case of cubic crystals. For crystals with tetragonal, trigonal, and hexagonal symmetry, the geometrical factors are given in the case of light propagating along the anisotropy axis. The dynamical selection rules are also reported. It is indicated how the two‐photon spectroscopy, using circularly polarized photons too, is able to lead to a complete experimental determination of the symmetry properties of the excited states in crystals.</jats:p>