Photorefractive parametric scattering in the ferroelectric relaxor SBN: Phenomenological and application aspects

Abstract

This paper is dedicated to the study of a new class of light-induced parametric scattering recently found in photorefractive Sr0.61Ba0.39Nb2O6:Cr (SBN:Cr). The scattering consists of polarization-isotropic cones induced by two pump beams and forming series of vertical lines on the observation screen. It is due to a type of 4WM processes between pump and scattering waves involving the fundamental grating recorded by the pump beams. A complete phenomenological analysis of the new 4WM model is presented. The scattering hysteresis under external fields and the temperature evolution of the new scattering are studied. It is shown that the parametric scattering is a useful tool for studying ferroelectric and relaxor properties of SBN.