Incoherently coupled grey-grey screening-photovoltaic soliton pairs in biased photovoltaic-photorefractive crystals

The incoherently coupled grey-grey screening-photovoltaic soliton pairs are predicted in biased photovoltaic-photorefractive crystals under steady-state conditions. These grey-grey screening-photovoltaic soliton pairs can be established provided that the incident beams have the same polarization, wavelength, and are mutually incoherent. Relevant example is presented where the photovoltaic-photorefractive crystal is of lithium niobate type. The grey-grey screening-photovoltaic soliton pairs can be considered as the united form of grey-grey screening soliton pairs and closed-circuit grey-grey photovoltaic soliton pairs. They reduce to grey-grey screening soliton pairs in the absence of photovoltaic effect, whereas they will become grey-grey photovoltaic pairs in the closed-circuit condition when the bias field is not applied.