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带输运模型方程和耦合波方程结合起来研究LiNbO3晶体中体全息记录和热固定的特性。发现在一边记录一边固定时,同时存在的离子光栅通过减小耦合增益而影响了电子光栅的写入,且得到的固定后折射率光栅随深度的改变较小,这与记录完固定有非常大的区别。两种热固定方法得到的折射率光栅的衍射效率大小将主要决定于入射记录光的初始光强比。该模型同时显示对于高掺杂浓度的LiNbO3晶体的热固定,在其显影过程中,由于导带电子有很大的弛豫率,因而无法擦除其中的电子光栅,这样得到的折射率光栅将只有很低的衍射效率。一系列的实验同时也证实了这一结论
Combined with transport model equations and coupled wave equations, the properties of holographic recording and thermal fixation in bulk LiNbO3 crystal were studied. It was found that while the record side was fixed, the simultaneous presence of the ion grating affected the writing of the electron grating by reducing the coupling gain, and the resulting change in the depth of the fixed refractive index grating was small, which was in agreement with the recording of a very large The difference The diffraction efficiency of the refractive index grating obtained by the two heat fixation methods will mainly depend on the initial light intensity ratio of incident recording light. The model also shows that for the high doping concentration of LiNbO3 crystal heat fixation during its development, due to conduction band electrons have a large relaxation rate, which can not be erased electron grating, the resulting refractive index grating will be Only very low diffraction efficiency. A series of experiments also confirm this conclusion