Steady-state screening-photovoltaic spatial solitons in the biased photorefractive-photovoltaic crystals

The theory of the screening-photovoltaic solitons is improved in biased pho torefractive-photovoltaic crystals. When the photovoltaic effect is negligi ble, the screening-photovoltaic solitons are the screening ones, and their space-charge held is the space-charge held of the screening solitons. If th e external field is absent, the screening-photovoltaic solitons are the pho tovoltaic ones on the open and closed-circuit conditions, and their space-c harge field is of the photovoltaic solitons. We also show theoretically tha t the screening and the photovoltaic solitons on the open- and closed-circu it conditions may be studies together as the screening-photovoltaic soliton s.