交流阻抗谱法研究高压下CdS的电学性质  

Electrical Properties of CdS Under High Pressure Using Alternating Current Impedance Spectroscopy

作　　者：贺春元[1] 刘丙国[1] 杨中娟[1] 朱红玉[1] 高春晓[2] 

机构地区：[1]河南理工大学物理化学学院,河南焦作454000 [2]吉林大学超硬材料国家重点实验室,长春130012

出　　处：《河南师范大学学报（自然科学版）》2011年第6期55-58,共4页Journal of Henan Normal University(Natural Science Edition)

基　　金：国家自然科学基金(10874053);吉林大学超硬材料国家重点实验室开放课题资助项目(201111);国家自然科学基金专项基金(11047109);河南理工大学博士基金(648428;648443)

摘　　要：利用金刚石对顶砧(DAC)原位交流阻抗谱测量技术,研究了硫化镉(CdS)半导体粉末在高压下的电输运性质.结果表明,在高压条件下CdS中存在两个电传导过程,晶体内传导和晶界传导,而晶体内传导是其主要过程.通过选择合适的表象,获得了CdS的体电阻随压力的变化关系,反映了CdS在高压下的相变过程:在2.7GPa～3.6GPa范围内,体电阻骤降了两个数量级,这对应着CdS从纤锌矿到岩盐矿的结构相变;在8GPa和14GPa附近,体电阻出现局域最大值,这对应着CdS从∑v→Xc到Lv→Xc的能带变化.另外实验结果预测在21GPa附近CdS的能带结构可能再次发生改变.By alternating current impedance spectroscopy basing on the technology of diamond anvil cell, the resears studyes the electrical transport properties of CdS powders under high pressure. The results indicate that there exist two electrical conduction processes in CdS, the grain interior conduction and grain boundary conduction, and the grain interior conduction is the main conduction process. By choosing a suitable representation the pressure dependence of the bulk resistance, is obtained which reflects the phase transitions of CdS under high pressure： the bulk resistance of CdS sharply drops two orders of magnitude from 2.7 GPa to 3.6 GPa, attributing to the structural phase transition from wurtzite to rocksalt structure; and appears two local maxima around 8 GPa and 14 GPa, assigned to the change of band gap from CdS从∑v→Xc to Lv→Xc Moreover, the experimental result indicates that the energy gap structure will change once more near 21 GPa.

关 键 词：金刚石对顶砧 交流阻抗谱 硫化镉 电阻 

分 类 号：O521.21[理学—高压高温物理]