不同二维拓扑模型的光电导行为研究

Studies of Optical Conductivities in Different Two-dimensional Topological Models

我们系统研究不同二维拓扑模型的光电导行为。我们发现,当质量项与动量无关时,光学带间跃迁导致霍尔光电导的实部和虚部分别出现跳变以及峰值行为。相反,当质量项与动量相关时,光学带间跃迁导致霍尔光电导的实部和虚部出现峰值以及跳变行为。这些现象为我们理解光电导的拓扑行为以及利用光学手段表征二维拓扑提供了理论指导。

We systematically study the optical conductivities in different two-dimensional topological models.We find that for models with momentum-independent mass term,optical interband transitions contribute to jumps and peaks in the real and imaginary parts of Hall conductivities.By contrast,for models with momentum-dependent mass term,optical interband transitions contribute to peaks and jumps in the real and imaginary parts of Hall conductivities.These phenomena provide theoretical guide to the understanding of topological behaviors of optical conductivities and the characterization of two-dimensional topology by optical approaches.