Bayaraa Temuujin, Xu Changsong, Yang Yali, Xiang Hongjun, Bellaiche L
Physics Department, University of Arkansas, Fayetteville, Arkansas 72701, USA.
Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville, Arkansas 72701, USA.
Phys Rev Lett. 2020 Aug 7;125(6):067602. doi: 10.1103/PhysRevLett.125.067602.
First-principles methods are employed to understand the existence of magnetic-domain-wall-induced electric polarization observed in rare-earth iron garnets. In contrast with previous beliefs, it is found that the occurrence of such polarization neither requires the local magnetic moments of the rare-earth ions nor noncollinear magnetism. It can rather be understood as originating from a magnetoelectric effect arising from ferromagnetic interactions between octahedral and tetrahedral Fe ions at the domain walls, and the mechanism behind is found to be a symmetric exchange-striction mechanism.
采用第一性原理方法来理解在稀土铁石榴石中观察到的磁畴壁诱导电极化的存在。与先前的观点相反，发现这种极化的出现既不需要稀土离子的局域磁矩，也不需要非共线磁性。相反，它可以被理解为源于畴壁处八面体和四面体铁离子之间铁磁相互作用产生的磁电效应，并且发现其背后的机制是一种对称交换收缩机制。
