铁电磁体Pb(Fe_(1/2)Nb_(1/2))O_3的磁电性能研究  

Magnetic and dielectric properties of ferroelectromagent Pb(Fe_(1/2)Nb_(1/2))O_3

作　　者：杨颖 李启昌[1] 刘俊明[1] 刘治国[1] 

机构地区：[1]南京大学固体微结构物理实验室

出　　处：《物理学报》2005年第9期4213-4216,共4页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:50332020;10021001;10374048);国家重点基础研究项目(批准号:2002CB613303)资助的课题.~~

摘　　要：对铁电磁体Pb(Fe12Nb12)O3单晶样品中的介电和磁性能进行了研究.认为在其反铁磁相变点观察到的介电常数和损耗的异常来自于自发极化序和自旋序的相互作用引起的磁电耦合.磁矩与温度的关系曲线在Nel点以下的低温段呈上升趋势,测得的磁滞回线证明有弱铁磁性出现.对铁电磁体磁电相互作用的MonteCarlo模拟得到与实验类似的结果.The magnetic and dielectric properties of the ferroelectromagnet（FEM） Pb（ Fe1/2Nb1/2 ）O3 （PFN） single crystals have been investigated. Anomalies in the dielectric constant as a function of temperature have been observed near its Néel temperature of - 143K, which are indicative of the so-called magnetoelectric coupling between the ferroelectric and antiferromagnetic orders in this compound. It is demonstrated that a weak magnetic transition appeared at the temperature a little below the Néel temperature, which confirms the earlier prediction from the Monte Carlo simulation in a qualitative sense. The magnetic hysteresis measurement proves that there does exists a weak magnetic order in PFN crystal below its Néel temperature.

关 键 词：铁电磁体 磁电耦合 磁电性能 单晶体 介电常数 磁滞回线 

分 类 号：O482.5[理学—固体物理]