主客体掺杂型非线性光学聚合物驻极体DR1/PMMA膜中空间和偶极电荷的相互作用特性

THE INTERACTION CHARACTERISTICS BETWEEN SPACE CHARGE AND DIPOLE IN THE HOST GUEST NLO POLYMER ELECTRET DR1/PMMA FILMS 

运用热刺激放电、表面电位衰减和电光效应的检测等手段，对主客体掺杂型非线性光学聚合物驻极体ＤＲ１／ＰＭＭＡ膜中空间和偶极电荷的相互作用特性进行了研究．结果表明，在极化后的样品中，被样品表面或体内的各类陷阱捕获的大部分空间电荷所处的陷阱能级高于极性生色团分子的定向排列产生的偶极电荷的束缚能级，空间电荷对偶极电荷有强烈的束缚作用．空间电荷衰减将导致材料内的电场分布发生变化，并引起极性生色团分子的松弛．

Abstract In this paper the interaction characteristics between space charge and dipole in the host guest nonlinear optical polymer electret DR1/PMMA films are studied by means of the open circuit thermal stimulate discharge(TSD) technique and measurements of the isothermal surface potential decay and the electro optical effect. The results indicate that there are two kinds of charges: space and dipole in the poled material, the energy level for most of the space charge trapped by the traps of sample is higher than the bound level of dipole charge originating from the dipole alignment after suitable heat treatment, and there is a strong interaction between space charge and dipole. The decay of space charge will cause the change of charge distribution in the materials, which subsequently leads to relaxation of the dipoles. The stability of space charge trapped in the material significantly affects the life of dipole alignment for the material.