论文标题
经典海森伯格抗fiferromagnets的刺猬晶状旋转纹理
Hedgehog-lattice spin texture in classical Heisenberg antiferromagnets on the breathing pyrochlore lattice
论文作者
论文摘要
已知刺猬晶格是磁性单翼和抗巨孔的三维周期性阵列，在存在Dzyaloshinskii-Moriya（DM）相互作用的情况下可以实现。在这里，我们通过蒙特卡洛模拟证明了刺猬晶格不是由DM相互作用引起的，而是在呼吸pyrochlore晶格上的经典海森伯格防反铁磁铁中的挫败感。在该模型中，呼吸键抗的特征是大四面体的最近邻邻（NN）抗磁磁交换相互作用与小型四面体的相互作用（J1'/j1）。具有Q =（\ pm 1/2，\ pm 1/2，\ pm 1/2）的四倍Q状态，用于实现沿债券方向沿债券方向的第三个第三nn nn抗铁磁相互作用实现，事实证明，在j1'/j1'/j1 cull in j1'/j 1'cull in Uns of j1''''in in Unse n in It n in Unse n in It n in Uns in Unse n in Unsip n in Unse n in Uns in Uns in Uns in Unse n in It n in Uns in n in Uns in n in Unse n in Uns.受热波动青睐的状态。还发现，在磁场中，（1/2,1/2,1/2）的结构从立方体变为四方，导致非零的净旋转手性，在金属系统中应产生特征性拓扑霍尔的效应。
The hedgehog lattice, a three-dimensional periodic array of magnetic monopoles and antimonopoles, is known to be realized in the presence of the Dzyaloshinskii-Moriya (DM) interaction. Here, we demonstrate by means of Monte Carlo simulations that the hedgehog lattice is induced by not the DM interaction but frustration in classical Heisenberg antiferromagnets on the breathing pyrochlore lattice. In the model, the breathing bond-alternation is characterized by the ratio of the nearest-neighbor (NN) antiferromagnetic exchange interaction for large tetrahedra to that for small ones, J1'/J1. A quadruple-q state with the ordering vector of q=(\pm 1/2,\pm 1/2,\pm 1/2), which is realized for a large third NN antiferromagnetic interaction along the bond direction J3, turns out to become the hedgehog-lattice state in the breathing case of J1'/J1 <1, while in the uniform case of J1'/J1 =1, it is a collinear state favored by thermal fluctuations. It is also found that in a magnetic field, the structure of the (1/2,1/2,1/2) hedgehog lattice is changed from cubic to tetragonal, resulting in a nonzero net spin chirality which in a metalic system, should yield a characteristic topological Hall effect.
