Separate spatial soliton pairs in biased series photorefractive polymer circuit

Abstract

This paper presents calculations based on the idea of photorefractive polymer spatial solitons, namely, screening solitons being formed in a biased series photorefractive polymer circuit consisting of two photorefractive polymer connected electronically by electrode leads in a chain with a voltage source. A system of two coupled equations is derived under appropriate conditions for two-beam propagation in the series photorefractive polymer circuit. The existence of dark-dark, bright-dark and bright-bright photorefractive polymer soliton pairs in such a circuit is proved. In the limit in which the optical wave has a spatial extent much less than the width of the photorefractive polymer, the two solitons in dark-dark soliton pairs can affect each other’s spatial profiles and the dynamical evolution by the light-induced current. For a bright-dark soliton pair, the dark soliton can affect the other soliton by light-induced current, but the bright soliton cannot. The two solitons in bright-bright soliton pairs cannot affect each other.