Abstract

KTP (KTiOPO₄) crystals exhibit excellent nonlinear optical properties in the visible range, for example, the large nonlinear coefficients and wide temperature and angular bandwidths. For the practical applications, however, optical absorption in the visible spectrum region (from 400 to 600 nm)^1,2 of KTP crystals must be reduced. In the present work, we report the substantial effects of an ambient on the optical absorption of KTP crystals during growth. Also, the dependence of the optical absorption on growth direction and impurity concentration in the crystal have been investigated. Characteristics and the origin of this optical absorption are discussed.

© 1995 IEEE