基于结模型的极化石英玻璃内建电场分析

用多载流子模型分析玻璃的热极化过程及其内部耗尽层的形成,极化电场的作用使载流子在玻璃内的迁移及由外界的注入最终形成交替的电荷分布,形成类似两个相向p-n结的结构。针对几种典型的p-n结电荷分布形式,计算了相应内建电场及二阶非线性极化率,极化完成后产生的宏观非线性效应主要由钠离子耗尽形成的突变结电场(~3′109V/m)决定,二阶非线性极化率的数值在0.2~1.2pm/V之间,耗尽区分布在阳极表面下25mm的范围。

Analysis of built-in field in poled fused silica using a junction model

The thermal poling process in silica and the formation of its depletion layer is analyzed by multi-carriers’ model. An alternating charge distribution is created by the injected and the shifted carriers in the silica, which is regarded as a structure with two opposite p-n junctions. The built-in electric fields, corresponding to the assumed carrier distributions inside the junctions, are cal-culated based on the junction model and compared with the published results. The generated nonlinearity is determined mainly by the induced built-in electric field （~3′109V/m） in the abrupt junction, c（2） values are with 0.2~1.2pm/V, and the depletion region is located within 25mm beneath the anode.