Temporal analysis of optical beams in biased photorefractive materials in the context of solitonic solutions: microscopic and macroscopic approach

Abstract

The validity of the commonly used time-dependent wave equation describing the propagation of screening one-dimensional solitons in photorefractive materials is discussed. Concentrating attention on temporal development of the space-charge field, we show that the widely used standard solution follows from a phenomenological description, which is consistent with the band transport model equations only in specific cases. The exact analytical solution for the localized optical beam is derived within the microscopic model under a low contrast approximation. The numerical modeling of photorefractive response to an arbitrary contrast is performed and compared with standard solutions. The range of applicability of the macroscopic approach for three basic classes of photorefractive crystals is discussed.