摘要
电导率测量的过程历经了从直流交流阻抗谱的过程,已经为地球物理学家借助于高温高压手段研究固体深部物质电学性质所广泛认同的。本文首先介绍了阻抗谱法测定水晶电导率的实验原理,进而采用该方法在10-1～106Hz的频率范围以及1.0～4.0GPa和823～1073K条件下,借助于YJ 3000t紧装式六面顶高压设备对沿Z轴方向生长的水晶进行了的电导率实验就位测量。实验结果表明:在选择的频率范围,样品的复阻抗的模和相角都对频率具有很强的依赖性;随着温度的升高,电阻迅速降低,电阻率降低,电导率增大;在压力1.0～4.0GPa,其活化焓分别为:0.8548eV、0.8320eV、0.8172eV、0.7834eV,独立于温度的指前因子分别为:1.003S/m、1.778S/m、3.082S/ m、6.987S/m,活化焓随着压力的升高而降低,指前因子随着压力的升高而增大。
It is broadly accepted that the measurements of the electrical conductivities endured from the direct current to alternating current to impedance spectra for most of the geophysicists. In the paper, the principle of impedance spectra was firstly introduced, and then electrical conductivities of the z-axis extension's quartz crystal were measured by virtue of SARLTON-1260 frequency and phase impedance spectroscopic analyzer under conditions of 1.0-4.0 GPa and 823-1073 K and in the range of 10-1-106Hz frequency. The experimental results indicate that the complex impedance spectra of the crystal strongly depend on frequency. The temperature is an important parameter deciding the electrical conductivity. As temperature increases, the electrical conductivity increases. The relationships between log σ and 1/T accord with Arrenhius relation formula. This is the first time that the pressure as a controlling ingredient is well brought forward: As the pressure increases, the block rate advances; at the same time the electrical conductivity decreases. In the range of 1.0-4.0 GPa of this experiment, the activation entropies are 0.8548 eV, 0.8320 eV, 0.8172 eV, 0.7834 eV, respectively and exponential genes are 1.003 S/m, 1.778 S/m, 3.082 S/m, 6.987 S/m, respectively. The activation entropy decreased with increase of pressure and the exponential gene increased with increase of pressure.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2005年第3期403-407,共5页
Journal of Synthetic Crystals
基金
中国科学院知识创新重要方向项目(KZCX3 SW 124)资助
关键词
水晶
高温高压
阻抗谱
活化焓
指前因子
quartz crystal
high temperature and high pressure
impedance spectra
activation entropy
exponential gene
