Fe:LiNbO_(3)晶体光折变全息热固定动力学特性分析

Dynamics Characteristic Analysis of Thermal Fixing Photorefractive Hologram Grating in Lithium Niobate

以 Fe:Li Nb O3晶体为例 ,考虑了电子载流子热激发 (强烈地依靠于温度 ) ,通过对以扩散和光伏特效应为主导输运机制的带输运方程和耦合波方程进行数值求解 ,分析了热固定过程初始光强入射比和固定温度对光栅空间电荷场的影响 ,指出记录固定过程中内电场极值的出现来源于质子电场对施主光栅电场的部分补偿 ,质子光栅电荷场可以导致晶体中记录光束之间能量耦合方向的变化 。

The standard band transport model with mobile ions and the coupled wave equation under different initial intensity ratio and fixing temperature are solved by numeric method to study the dynamics of recording and thermal fixing photorefractive hologram at high temperature in LiNbO 3 photorefractive crystal. The theoretical thermal fixing time and the temperature dependence of the space charge field are obtained. During of recording and fixing the partial cancellation of proton grating and the donor grating causes the emergency of the net charge field’s extremum, and proton grating could also change the direction of the coupling between the reference light and the signal light.