高电场下弛豫铁电体的场致效应  

Field induced effect of relaxor ferroelectrics at high electric field

作　　者：陈勇[1] 卞梦云 张灿灿[1] 陈琪[1] 骆迁 黄镇[1] 曹万强[1,2] 潘瑞琨[1,2] 祁亚军[1,2] CHEN Yong BIAN MengYun ZHANG CanCan CHEN Qi LUO Qian HUANG Zhen CAO WanQiang PAN RuiKun QI YaJun(Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials, Key Laboratory ofFerro ＆ Piezoelectric Materials and Devices of Hubei Province, School of Physics and Electronic Science, Hubei University, Wuhan 430062, China School of Materzals Sctence and Engzneermg, Hubei University, Wuhan 430062, China)

机构地区：[1]湖北大学物理与电子科学学院,铁电压电材料与器件湖北省重点实验室,有机化工新材料湖北省协同创新中心,武汉430062 [2]湖北大学材料科学与工程学院,武汉430062

出　　处：《中国科学：技术科学》2017年第1期32-38,共7页Scientia Sinica(Technologica)

基　　金：湖北省教育厅重点科学技术研究(编号:D20161006)资助项目

摘　　要：弛豫铁电体在热释电、介电、电场调制微波器件和电致伸缩器件方面有着广泛的应用.这些应用均涉及电场的作用.因电场会导致极化强度增大,并连续地延伸到顺电相,从而产生了电场诱导效应.用弯曲近似法对极化强度在电场作用下随温度的连续变化做近似,得到了介电系数峰值在高场下随电场2/3次方的变化规律.与介电峰在电场作用下移动的实验结果基本一致.理论数值模拟发现:存在一个与热力学参量相关的极化温度系数,其值越大,场致介电移峰效应越小,且热释电系数越大;反之,如果场致介电移峰效应越大,电场调制微波器件的介电可调性及可调性的温度稳定性会越好.上述研究结果对掺杂改性研究微波器件的介电可调性和热释电性有一定的参考作用.Relaxor ferroelectrics have been widely used in dielectric, pyroelectric, electric field modulation microwave devices and electrostriction device. These applications refer to effect of electric field, increase in strength of polarization from ferroelectric phase stretching to paraelectric phase successively, to give rise to an effect similar to field induced effect. A result of the peak temperature of dielectric permittivity changing with the electric field 2/3 power was obtained by using approximation method, which is coincident with the experimental result of dielectric peak. The numerical simulation results found that there exist a thermal dynamics related polarization-temperature coefficient. Increasing the coefficient will decrease shift effect of dielectric peak, or will decrease effect of field induced phase transition, but, will increase pyroelectric effect. On the contrary, the stronger shift effect of dielectric peak will increase dielectric tunability and its temperature stability for electric field modulated microwave devices. The above theoretic results have certain reference implications for dielectric tunability of microwave device and pyroeleetric property by doping modification method.

关 键 词：铁电体 场致效应 热释电系数 介电可调性 

分 类 号：TM221[一般工业技术—材料科学与工程]