Ho_(0.5)Pr_(0.5)FeO_3的磁性与巨磁介电效应  

Giant Magnetodielectric Effect and Magnetic Properties of Ho_(0.5)Pr_(0.5)FeO_3 Ceramics

作　　者：谢慧[1] 袁淑娟[1] 康保娟[1] 鲁波[2] 曹世勋[1] 张金仓[1] 

机构地区：[1]上海大学物理系,上海200444 [2]上海大学微结构实验室,上海200444

出　　处：《无机材料学报》2014年第1期77-80,共4页Journal of Inorganic Materials

基　　金：国家自然科学基金(11274221;50932003;11074163);上海市教育委员会科技创新项目(12YZ018)~~

摘　　要：采用固相反应法制备了Ho0.5Pr0.5FeO3多晶样品, 对其磁性和磁介电特性进行了系统研究。在T=4.5 K附近存在Ho离子的反铁磁相变, 在T= 59 -80K可观测到Fe离子的自旋重取向转变, 磁滞回线表明样品呈现弱铁磁性。在T= 270 K, 介电常数可达-103, 研究表明该介电常数与270 K附近的电阻变化相关联, 该处电阻变小, 介质损耗减小, 导致介电值变大。尤其重要的是, 该样品在室温下表现出磁场诱导的巨磁介电效应, 在频率 kHz、外加磁场为1.6×106 A/m下, 其值可达5500%, 该巨磁介电效应可能来源于磁电阻效应。Polycrystalline sample Ho0.5Pr0.5FeO3 was prepared by a solid state reaction method. The magnetic properties and magnetodielectric effect of the sample were investigated. The results show that the Ho3＋ antiferromagnetoly orders at T=4.5 K and the Fe3＋ spin reorientation transition occurs at 59-80 K. The sample exhibits a colossal dielectric constant value of ~103 around 270 K, which is correlated with a resistance transition at 270 K. The decrease of the resistance and the dielectric loss lead to the increase of the dielectric constant. Most importantly, a magnetic field of 1.6×106 A/m can induce a giant magnetodielectric response of 5500% under？kHz at room temperature. The giant magnetodielectric effect might come from the magnetorisistance effect.

关 键 词：磁介电效应 介电常数 固相反应 自旋重取向 

分 类 号：TQ174[化学工程—陶瓷工业]