Magnetic and ferroelectric properties of multiferroic RMn2O5
Magnetic and ferroelectric properties of multiferroic RMn2O5
复制标题
DOI：
10.1088/0953-8984/20/43/434206
复制
发表时间：
2008-10-29
影响因子：
2.7
通讯作者：
Kohn, K.
中科院分区：
文献类型：
--
作者：
Noda, Y.;Kimura, H.;Kohn, K.
根据最近的中子衍射和介电测量结果，综述了多铁性RMn_2 O_5（R = Y，Tb，Ho，Er，Tm）的磁性和铁电性质。磁有序和介电有序的连续相变被发现同时发生在该系统中。该系统的特征磁有序表现出一个inexaminate-commonly相变，并再次过渡到一个非公度相。特别注意的磁结构，以讨论引入铁电极化的机制。对于所有的化合物检查，自旋配置为Mn 4+和Mn 3+离子在相称的磁相，其中发生自发电极化，被确定为横向螺旋自旋结构传播沿着c轴。相反，R3+离子的诱导4f矩的排列显示出变化，这取决于每个元素的特性。在低温下对外场（如磁场、静水压力等）的相应响应强烈依赖于RMn_2 O_5体系中存在的稀土元素。该体系中的庞磁电效应可以很容易地用从磁无公度弱铁电相到公度铁电相的相变来解释。
The magnetic and ferroelectric properties of multiferroic RMn2O5 (R = Y, Tb, Ho, Er, Tm) are reviewed based on recent neutron diffraction and dielectric measurements. Successive phase transitions of magnetic and dielectric ordering were found to occur simultaneously in this system. The characteristic magnetic ordering of the system exhibits an incommensurate-commensurate phase transition, and again transitions to an incommensurate phase. Special attention is given to the magnetic structure in order to discuss the mechanism for the introduction of ferroelectric polarization. For all the compounds examined, the spin configuration for Mn4+ and Mn3+ ions in the commensurate magnetic phase, where spontaneous electric polarization occurs, was determined to be a transverse spiral spin structure propagating along the c-axis. By contrast, the alignment of the induced 4f moment of R3+ ions showed variation, depending on the character of each of the elements. Corresponding responses to external fields such as a magnetic field, hydrostatic pressure etc at low temperature are strongly dependent on the rare earth element present in the RMn2O5 system. The so-called colossal magnetoelectric effect in this system can be easily interpreted by the phase transition from the magnetic incommensurate and weak ferroelectric phase to the commensurate and ferroelectric phase.