Abstract

The photorefractive effect has been intensively studied for its wide range of potential applications. Photorefractive crystals are insulators exhibiting both photoconductivity and electrooptic effect. The light induced redistribution of charge carriers generates a space charge field that modulates the refractive index. The simple model in which a single type of charge carriers are excited from and recombined to a single type of sites has been described many times. It/as been improved by introducing either new sites or both types of carriers. The experimental verifications that have been performed with nanosecond light pulses (BSO, BaTiO₃ , LiNbO₃) or picosecond light pulses (GaAs, BaTiO₃) always led to a build up of the photo- refractive grating within the pulse duration.

© 1988 Optical Society of America