Study On Holographic Photovoltaic Solitons In Photorefractive Crystals With Both The Linear And Quadratic Electro-Optic Effects

Photorefractive spatial optical soliton has important application value in all-optical switching,optical interconnection,optical information processing,etc.Studies have found that linear electro-optic effects and secondary electro-optic effects can exist in some photorefractive crystals at the same time,so it is of great significance to study the formation of spatial optical solitons in photorefractive crystals when these two properties exist at the same time.The main purpose of this thesis is to study the holographic photovoltaic solitons in photovoltaic photorefractive crystals when linear and secondary electro-optic effects coexist.The thesis starts from the Helmholtz equation satisfied by the signal photoelectric field component and the belt transport model of describe photorefractive effect was proposed by Kukhtarev et al.and the two-wave coupling theory,and finds the coexistence of linear and quadratic electro-optical effects under closed-circuit conditions.The dynamic evolution equation of the holographic photovoltaic soliton in the photovoltaic photorefractive crystal.And the solution of the integral form of the bright and dark holographic photovoltaic soliton when the two effects coexist is given by calculation.Then the formation of the soliton is taken as an example of the lithium niobate crystal Conditions and properties are analyzed by numerical simulation.According to the research process of holographic photovoltaic soliton under closed circuit condition,the dynamic evolution equation of holographic photovoltaic soliton under open circuit condition is deduced,and then the solution of bright and dark holographic photovoltaic soliton under open circuit condition is given.Then,the evolution characteristics of bright and dark solitons are simulated and analyzed according to the soliton solution.Finally,the holographic photovoltaic solitons in the photovoltaic photorefractive medium where the linear and secondary electro-optic effects coexist in the Hamilton system and the dissipative system are analyzed and discussed under the small amplitude approximation.The transmission equation of soliton in Hamiltonian system and dissipative system is derived.For the Hamiltonian system,the influence of incident light intensity,photovoltaic field intensity and secondary electro-optic effect on bright and dark solitons is discussed.For dissipative systems,mainly soliton three cases when the gain and loss is balanced analyze simulation.