Transmission Properties Of Photorefractive Surface Waves Under Drift And Diffusion Mechanism

Photorefractive effect is light-induced refractive index change. The refractive index of the electro-optic materials is changed under the radiation of non-uniform light intensity. Even in weak light intensity, we can also get sufficiently large refractive index change as long as radiation time long enough. Nonlinear optics and surface science were connected closely by the study photorefractive surface waves. The energy of surface waves is concentrated in a narrow surface space layer of the photorefractive crystal, so surface nonlinear optical effect is significantly enhanced.The theory research of photorefractive nonlinear waves under diffusion mechanism has formed a relatively mature theory system, and the research of photorefractive nonlinear waves under photovoltaic is still at preliminary exploration. Research in photorefractive nonlinear surface waves under diffusion-drift mechanism has not yet formed a unified theoretical system. Generally, people study the mechanism with analytic methods or numerical simulation methods. We chose the analytical method to study, because the numerical method would need a lot of time and resources.It was found that surface waves in a crystal surface produce self-bending dynamic process. In order to study the physical properties of photorefractive surface waves in more detail. We studied the analytical solution of the nonlinear Schrodinger equation based on soliton self-bending effect of photorefractive surface waves under diffusion-drift mechanism. Firstly, we introduced the field, the methods and the development. And we had a brief introduction in the photorefractive effect theory, including the principles, characteristics, migration mechanisms and the band transport model. The work described the mechanism of optical soliton and analyzed in detail the physical model, and the self-bending process of surface waves. Afterwards, we led into the nonlinear Schrodinger equation of photorefractive nonlinear surface waves under diffusion-drift mechanism and the Hirota bilinear method, and solved the equation with the method. We used the improved Hirota bilinear method because the solution does not show soliton self-bending process, and the equation was solved with the improved method. Finally, We studied the effect of diffusion and drift mechanisms on surface waves transmission properties, as well as oblique incidence on the self-bending dynamic process of surface waves.