Y_(0.75)Ca_(0.25)MnO_3体系的自旋玻璃行为与输运特性研究  

Spin-glass behavior and transport properties for Y_(0.75)Ca_(0.25)MnO_3 system

作　　者：李越峰[1] 张玉凤[1] 曹世勋[1] 敬超[1] 张金仓[1] 

机构地区：[1]上海大学物理系,上海200444

出　　处：《功能材料》2007年第1期43-46,共4页Journal of Functional Materials

基　　金：国家自然科学基金资助项目(10574087);高等学校博士学科点专项科研基金资助项目(20050280004);上海市科委重点基础研究资助项目(04JC14039);上海市重点学科资助项目(T0104)

摘　　要：研究了Y0.75Ca0.25MnO3体系的结构和电磁特性,结果表明,场冷(FC)和零场冷(ZFC)直流磁化曲线在低温下存在典型的分叉现象,相应的Tcusp=34K;不同频率下交流磁化测量表明了随着频率的增加自旋冻结温度Tf=Tcusp向高温区移动,结合电输运测量,证明Y0.75Ca0.25MnO3体系为一典型的自旋玻璃绝缘(SGI)体系。The structure and electromagnetic properties of perovskite manganite Y0.75 Ca0.25 MnO3 were systematically investigated. In low temperatures, a typical behavior of bifurcation was observed between field-cooled （FC） and zero-field-cooled （ZFC） magnetization with a cusp at Tcusp =34K in the ZFC magnetization curve. AC susceptibility also showed a cusp at Tf= Tcusp, called spin-glass freezing temperature, which shifts to high temperature with increasing frequencies. With the resistivity behavior in the electrical transport measurement, we considered an intrinsic spin-glass insulator （SGI） in the Y0.75 Ca0.25 MnO3 system.

关 键 词：钙钛矿锰氧化物 自旋玻璃 不可逆性 

分 类 号：O469[理学—凝聚态物理]