Experimental determination of the electro-optic coefficients in Ba0.77Ca0.23TiO3

We propose an experimental method for the determination of the electro-optic coefficients of photorefractive crystals. Using anisotropic properties of the crystal and using the response of the crystal to different polarization states of the incident light, it is possible to determine the ratio between various electro-optic coefficients by measuring the gain in a two-wave mixing set-up. The accuracy of the measurements is estimated and the obtained electro-optic coefficients for a Ba_0.77Ca_0.23TiO₃ crystal show good agreement with corresponding values already known from the literature. Received: 24 January 2000 / Revised version: 23 May 2000 / Published online: 16 August 2000