Coupled spatial periodic waves and solitons in the photovoltaic photorefractive crystals

The evolution of spatial solitons in the photovoltaic photorefractive crystal can be governed by the specific coupled nonlinear Schrodinger equations. Under the photovoltaic field with the external bias field, the coupled cn-sn-type periodic wave solution and the corresponding photorefractive bright-dark soliton pair were constructed to describe the evolution of beam. The influence of the external bias field on solitonic dynamics is analyzed. In the photovoltaic crystal, coupled sn-cn-type, sn-dn-type periodic wave solutions, solution constructed by products of elliptic functions and the corresponding dark-bright soliton pair and coupled double-peaked soliton solutions are found to describe the evolution of a spatial-phase-modulated photovoltaic soliton and a non-phase-modulated beam.