| 报告题目 | Semiclassical Theory of Bloch Electrons up to Second Order in Electromagnetic Fields |
| 报告人 | 高洋 |
| 报告人单位 | Department of Physics,The University of Texas at Austin |
| 报告时间 | 2014-06-09 |
| 报告地点 | 合肥微尺度物质科学国家实验室九楼会议室 |
| 主办单位 | 合肥微尺度物质科学国家实验室、国际功能材料量子设计中心 |
| 报告介绍 | Abstract: The first order semiclassical theory is a powerful and intuitive tool to understand the behavior of Bloch electrons (AHE, ANE, etc). The key ingredients are the orbital magnetic moment and Berry-curvature-induced anomalous velocity. However, the first order semiclassical theory is insufficient to derive various second order response functions. Here, I will introduce a semiclassical theory accurate up to second order in external fields by generalizing the wave packet formalism. The equations of motion have the same form as in the first order theory. However, the Berry curvature is modified by the curl of a new concept called positional shift. Also, corrections to the semiclassical energy are classified into three categories. For applications, the magnetoelectric polarizability, the nonlinear anomalous Hall effect and the magnetic susceptibility are discussed. |
