反铁电体的能量释放效应  

Energy release effect in antiferroelectrics

作　　者：曹万强[1] 乐耀昌 陈勇 郑克玉[1] 潘瑞琨[1] 王龙海[1] CAO WanQiang;YUE YaoChang;CHEN Yong;ZHENG KeYu;PAN RuiKun;WANG LongHai(Key Laboratory of Ferro&Piezoelectric Materials and Devices of Hubei Province,Hubei Collaborative Innovation Center for Advanced Organic Chemical Materials,Key Laboratory of Ministry of Education for the Green Preparation and Application of Functional Materials,School of Materials Science and Engineering,Hubei University,Wuhan 430062,China;School of Physics and Electronic Science,Hubei University,Wuhan 430062,China)

机构地区：[1]湖北大学材料科学与工程学院,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,功能材料绿色制备与应用教育部重点实验室,武汉430062 [2]湖北大学物理与电子科学学院,武汉430062

出　　处：《中国科学：物理学、力学、天文学》2020年第6期115-122,共8页Scientia Sinica Physica,Mechanica & Astronomica

摘　　要：基于唯象理论得到的反铁电体电滞回线的温度关系,系统地研究了二阶相变反铁电体在增加和撤消电场过程中能量释放的温度关系.研究结果显示,反铁电体所释放的能量密度在温度谱有两个峰,高温的大峰在顺电相,其温度略高于居里温度;在反铁电相的低温区还存在一个小峰:当温度从居里温度下降时释放的能量密度会逐步增大到峰的顶点,之后缓慢下降.该结论与大量的实验结果一致.吉布斯自由能的两个参数对可逆能量密度峰的温度宽度和高度均有重要影响:极化强度二次方的系数越小能量密度峰的温度宽度越宽;四次方的系数越小能量密度峰的高度越高;它们支配了反铁电体的极化强度、能量特性和介电常数.本文研究了热力学参数对介电常数峰与能量密度峰的综合影响,并发现两者存在密切的关联效应.The energy release effect is an effect that happens during the process of withdrawing the electric field after charging electric energy into the materials,which can be represented by the amount of recoverable energy storage density.On the basis of the previously derived relationship between the antiferroelectric hysteresis loop with temperature from the phenomenological theory by considering two different responses of the two polarizations in opposite directions to an applied electric field,the relationship between the recoverable energy storage density with temperature during the process of withdrawing the electric field is systemically studied in the second-order phase transition antiferroelectrics.The results show that there are two peaks of the recoverable energy storage density in the temperature spectrum:the smaller energy density peak is in the antiferroelectric phase,and the other larger peak is in the paraelectric phase at the temperature slightly higher than the Curie temperature.When the temperature decreases from the Curie temperature,the recoverable energy storage density will gradually increase to the smaller peak and then slowly decrease.This conclusion is consistent with many experimental results on antiferroelectric materials including ceramics,thin films,and single crystals.The further analysis of the effect of the Gibbs free energy on the energy release effect shows that the two coefficients of the Gibbs free energy are essential for the width and height of the peak of recoverable energy storage density.Specifically,the smaller is the coefficient of the quadratic power of polarization,the wider is the temperature width of the peak,or temperature stability,the smaller is the coefficient of the fourth power of polarization,and the higher is the height of the released energy peak.These two parameters dominate the behaviors of polarization,energy storage characteristic,and the dielectric constant of the antiferroelectrics,and establish the correlation between the dielectric constant peak and the hi

关 键 词：反铁电体 储能效应 极化强度 介电常数 

分 类 号：TN384[电子电信—物理电子学]