论文标题
量子异常效应以外的磁绝缘体中的一般非线性霍尔电流
General nonlinear Hall current in magnetic insulators beyond the quantum anomalous Hall effect
论文作者
论文摘要
通用磁绝缘子可以表现出大厅电流吗？量子异常霍尔效应（QAHE）是携带量化霍尔电导率和其他绝缘子（零chern数）的绝缘散装的一个例子，在线性响应方面呈现零霍尔电导。在这里，我们发现，如果系统破坏反转对称性，则一般的磁绝缘子具有非线性霍尔电导率二次与电场。该电导率源于由于虚拟间跨跃迁引起的诱导轨道磁化。我们确定了对波袋运动的三个贡献，速度转移，位置转移和浆果曲率的重新归一化。与晶体固体相反，我们发现这种非线性霍尔电导率消失了2D电子气体的Landau水平，表明Qahe和Integer量子大厅效应之间存在基本差异。
Can a generic magnetic insulator exhibit a Hall current? The quantum anomalous Hall effect (QAHE) is one example of an insulating bulk carrying a quantized Hall conductivity and other insulators (with zero Chern number) present zero Hall conductance in the linear response regime. Here, we find that a general magnetic insulator possesses a nonlinear Hall conductivity quadratic to the electric field if the system breaks inversion symmetry. This conductivity originates from an induced orbital magnetization due to virtual interband transitions. We identify three contributions to the wavepacket motion, a velocity shift, a positional shift, and a Berry curvature renormalization. In contrast to the crystalline solid, we find that this nonlinear Hall conductivity vanishes for Landau levels of a 2D electron gas, indicating a fundamental difference between the QAHE and the Integer quantum Hall effect.
