Microscopic and phenomenological theory of the dynamics of screening photorefractive solitons

Abstract

The theory of photorefractive (PR) screening solitons is regarded as a well-established theory and solidly confirmed experimentally. In this paper we focus main attention on the dynamics of bright and dark beams in PR crystals in the context of soliton generation. The analysis was carried out within the microscopic theory in opposition to the commonly used macroscopic theory. It has been shown that the standard solution may be drastically different from the solution based on the microscopic model. This paper presents a new formulation of the adiabatic approximation and the corresponding temporal equation for the formation of the electric field in PR crystals. A novel time constant has been introduced to describe the total duration of the transition state. The obtained results were compared with numerical solutions. In this way, we developed a description of the dynamics of (1+1)D beams in PR materials consistent with the microscopic model.