论文标题
共线II型多表情中的拓扑孤子和大量极化开关
Topological solitons and bulk polarization switch in collinear type II multiferroics
论文作者
论文摘要
我们引入了一个微观模型，用于磁性挫败感和易于轴各向异性，以繁殖能够繁殖的类似的“ UUDD”（或反相）磁性排序在几种II型多毛发材料中观察到。晶格扭曲在这些材料的多性特征中的关键作用通过间接磁电耦合输入到模型中，该耦合是通过弹力仪机制介导的，由弹性自由度介导。远距离偶极相互作用将电偶极子设置为抗抗逆火一星。我们通过广泛的DMRG计算和互补分析方法研究了该模型。我们表明，晶格二聚化诱导自发的Z2 ferrielectric散装极化，其急剧开关由临界值高于临界值的磁场产生。磁激发的拓扑特征使得这种机制可靠。
We introduce a microscopic model for collinear multiferroics capable to reproduce, as a consequence of magnetic frustration and easy-axis anisotropy, the so-called "uudd" (or antiphase) magnetic ordering observed in several type II multiferroic materials. The crucial role of lattice distortions in the multiferroic character of these materials is entered into the model via an indirect magnetoelectric coupling, mediated by elastic degrees of freedom through a pantograph mechanism. Long range dipolar interactions set electric dipoles in the antiferroelectric order. We investigate this model by means of extensive DMRG computations and complementary analytical methods. We show that a lattice dimerization induces a spontaneous Z2 ferrielectric bulk polarization, with a sharp switch off produced by a magnetic field above a critical value. The topological character of the magnetic excitations makes this mechanism robust.
