一种测定某些离子导体的导电基本参数的新方法

利用低频交变电场在某些离子导体中能引起偏振态改变的光衍射特性,发展了一种测量这些离子导体的导电基本参数的新方法,并且用它测定了α-LiIO₃单晶的基本离子导电参数,测得其载流子的迁移率激活能E_μ=0.36eV;夫仑克耳缺陷的形成能为E_M=0.59eV;300K时正、负载流子的数密度均为1.6×10¹⁷cm^-3,相对浓度均为1.07×10^-5;当所加电场反平行于晶体的自发极化强 关键词：

A NEW METHOD APPLIED TO SOME IONIC CONDUCTORS FOR MEASURING PARAMETERS OF IONIC CONDUCTION

In this paper, a new method applied to some ionic conductors for measuring fundamental parameters of ionic conduction was developed based on the phenomena of light diffraction produced by a laser beam through these ionic conductors under a low frequency AC field. The ionic conduction parameters of aaaa-LiIO₃ single crystal was measured by this method. The results are as follows. The activation energy of mobility E_μ=0.36eV. The formation energy of Frenkel defect E_M =0.59 eV. At 300K, both the number densities of positive and negative carriers are 1.6×10¹⁷cm^-3; their relative concentrations are 1.07×10^-5; the effective mobility μ_eff⁺=3.9×10^-8cm²·s^-1·V^-1 as the DC field applied to the crystal is antiparallel to its spontaneous polarization (we denote the voltage as V₊) the effective mobility μ_eff^- = 3.4 ×10^-9cm²·s^-1·V^-1 as they are parallel (we denote the voltage as V_-). Under the action of an AC field, in the half period that is corresponding to V₊, it at least need that the ion hops 7 steps to form a space grating, and in another half period ion at least hops 32 steps to cause an oscillating component in the diffraction light intensity.