FeV2O4多晶块材的磁电效应与输运特性
黄思俞1*,王宗篪1,郑冬梅1,王宇航2

(1.三明学院机电工程学院,福建 三明 365004; 2.清华大学物理系,北京 100084)

FeV2O4多晶块材; 尖晶石结构; 磁电效应; 交流阻抗谱

Magnetoelectric Effect and Transport Properties of FeV2O4 Polycrystal Bulk
HUANG Siyu1*,WANG Zongchi1,ZHENG Dongmei1,WANG Yuhang2

(1.School of Mechanical and Electrical Engineering,Sanming University,Sanming 365004,China; 2.Department of Physics,Tsinghua University,Beijing 100084,China)

FeV2O4 polycrystal bulk; spinel structure; magnetoelectric effect; AC impedance spectroscopy

DOI: 10.6043/j.issn.0438-0479.201607013

备注

采用固相烧结法制备了FeV2O4多晶块材,采用X射线衍射法和电子显微镜断面扫描对FeV2O4多晶块材进行结构表征,并测量其铁电极化强度和交、直流电输运特性.结果表明,制备的FeV2O4多晶块材是纯净的,结构较致密.低温(6 K)时FeV2O4多晶块材的铁电饱和极化强度达到141.8 μC/m2,外加磁场后自发极化强度受到较大的压制,表明样品具有较强的磁电效应,其最大磁阻效应(2.83%)出现在亚铁磁转变温度TN1(110 K)处.结合交流阻抗谱辅助等效回路分析法,对测量数据进行拟合.结果显示FeV2O4多晶块材的直流和交流输运特性都符合Mott的变程跳跃(variable range hopping,VRH)机制,其能带是近似于原子能级的窄带.

FeV2O4 polycrystal bulk was prepared using solid state sintering method.The microstructure of the sample was characte-rized with X-ray diffraction spectroscopy and scanning electron microscopy.The ferroelectric polarization and AC and DC transport properties were measured.The results show a pure phase and dense structure of the sample.A polarization of the sample as large as 141.8 μC/m2 was observed at low temperature(6 K).Moreover,the polarization was greatly suppressed by the magnetic field,indicating an obvious magnetoelectric effect.The magnetoresistance effect of the sample shows the maximum value of 2.83% at the ferromagnetic transition temperature TN1(110 K).By fitting the results with equivalent circuit method,it is found that both AC and DC tran-sport characteristics of the FeV2O4 sample are in accordance with the Mott variable range hopping(VRH)mechanism,suggesting the narrow band of the sample similar to that of the atomic level.