Abstract

KNbO₃ crystals doped with Co have been grown by the Kyropoulos method. The density of Co ions in the crystal is about 100 parts in 10⁶. The inhomogeneity of refractive index Δn < 10⁻⁵/cm. The ordinary dimensions of single-domain KNbO₃:Co crystals are about 10 × 10 × 10 mm³. Photorefractlve properties of KNbO₃:Co have been compared with those of KNbO₃:Fe. It has been found that the photorefractive diffraction efficiency of KNbO₃:Co crystal without being reduced is one order of magnitude larger than that of reduced KNbO₃:Fe crystal. The two wave coupling intensity distribution with the change of entering direction of the laser beam has been measured, and the distribution curve has been given. Other photorefractive experiments are being carryied out, and the results will be reported.

© 1992 Optical Society of America