Yasuo TOMITA and Akihiro SUZUKI

Electronics Engineering Department, University of Electro-Communications, 1-5-1, Chofugaoka, Chofu, Tokyo, 182 Japan

(Accepted August 25, 1994)

Two-beam coupling gain and speed of Cr-doped strontium barium niobate in the visible and near-infrared spectral regions are measured. It is found that the sample still exhibits the appreciable photorefractive gain in the near-infrared spectrum. Photorefractive parameters such as effective trap density, effective electrooptic coefficient and mobilityEˇrecombination-time product are obtained from the measurement. The photorefractive spectra of the coupling gain and speed in the sample are compared with those of Cr-doped KNSBN.

Key words : photorefractive effect, two-beam coupling, electrooptic effect, ferroelectric crystals, strontium barium niobate