Optical properties of lithium indium selenide

Conditions of growth of LiInS2 and LiInSe2 crystals with high optical quality are studied. Data on the dispersion of refractive indices in red-phase LiInSe2 crystals are presented. Possible nonlinear three-frequency processes in LiInS2 and LiInSe2 crystals used for SHG and OPO are analyzed. Potentials of these crystals for application in OPO devices are shown.