Abstract

1. Introduction The stoichiometric influence on the photorefractive properties of LiTaO₃ has been the subject of intensive research in the recent past. It has been reported that the domain switching behaviour is directly related with the nonstoichiometric defect density in LiTaO₃.¹ The extrinsic impurities are known to alter the photoconductive and photogalvanic properties. However, it is of special interest to study the influence of intrinsic defects, due to nonstoichiometry, on these properties. Recently, Jazbinsek et al.² have investigated the wavelength dependence of photorefraction in near-stoichiometric LiTaO₃. It has been observed that the spatial charge field causing a beam fanning is suppressed under the irradiation of UV light because of the increase in photoconductivity under the UV irradiation. In this investigation, the polarization and wavelength dependence of photogalvanic current and photoconductivity has been studied for LiTaO,.Two different wavelengths (532 nm green and 350 nm UV lights) have been used. In order to study the optical damage, a focused beam of 532 nm green laser was used.

© 2002 Optical Society of America