Bright pyroelectric quasi-solitons in a photorefractive waveguide

Characteristics of propagation of bright pyroelectric quasi-solitons are studied in a photorefractive waveguide. These solitons considered are supported solely by the pyroelectric effect. The investigation is performed under Wentzel-Kramers-Brillouin-Jefferys approximation and a Gaussian ansatz for the soliton is used instead of numerical solutions. The planar waveguide structure intensifies the self-focussing while decreasing the minimum or threshold power required for self trapping. The waveguide structure embedded in the crystal can self trap a soliton of power lower than the threshold power. As the waveguide parameter increases, minimum required power to self trap the beam decreases. The existence of bistable states is also predicted. Four regimes of power are identified and investigated in which the quasi-solitons behaviour is distinct.