论文标题
半导体纳米结构中的拓扑磁电效应：量子井，电线，点和环
The topological magnetoelectric effect in semiconductor nanostructures: quantum wells, wires, dots and rings
论文作者
论文摘要
普通绝缘子和拓扑绝缘子之间的界面附近放置的静电电荷通过所谓的拓扑磁电效应诱导磁场。在这里，我们提出了关联的麦克斯韦方程的数值实现。所得模型与图像充电方法一样简单，快速和定量，但在追求特定效果时可以轻松访问精心制作的几何形状。该模型用于研究磁电场如何受到最常见的半导体纳米结构的尺寸和形状的影响：量子井，量子线，量子点和量子环。点状电荷产生了MT的磁场，其符号和空间取向受纳米结构的几何形状和电荷位置的控制。结果通过在表面上引起的大厅电流而合理化，这构成了磁电场确定性设计的简单而有效的框架。
Electrostatic charges placed near the interface between ordinary and topological insulators induce magnetic fields, through the so-called topological magnetoelectric effect. Here, we present a numerical implementation of the associated Maxwell equations. The resulting model is simple, fast and quantitatively as accurate as the image charge method, but with the advantage of providing easy access to elaborate geometries when pursuing specific effects. The model is used to study how magnetoelectric fields are influenced by the dimensions and the shape of the most common semiconductor nanostructures: quantum wells, quantum wires, quantum dots and quantum rings. Point-like charges give rise to magnetic fields of the order of mT, whose sign and spatial orientation is governed by the geometry of the nanostructure and the location of the charge. The results are rationalized in terms of the Hall currents induced on the surface, which constitute a simple yet valid framework for the deterministic design of magnetoelectric fields.
