Du Tao, Li Yue-Xun, Li Yan, Lu He-Lin, Zhang Hui
Department of Physics, Yunnan Minzu University, Kunming 650500, People's Republic of China.
J Phys Condens Matter. 2017 Sep 27;29(38):385601. doi: 10.1088/1361-648X/aa7a86. Epub 2017 Jun 20.
The dimerized Kane-Mele model with/without strong interaction is studied using analytical methods. The boundary of the topological phase transition of the model without strong interaction is obtained. Our results show that the occurrence of the transition only depends on dimerized parameter [Formula: see text]. From the one-particle spectrum, we obtain the completed phase diagram including the quantum spin Hall state and the topologically trivial insulator. Then, using different mean field methods, we investigate the Mott transition and the magnetic transition of the strongly correlated dimerized Kane-Mele model. In the region between the two transitions, the topological Mott insulator with characteristics of Mott insulators and topological phases may be the most interesting phase. In this work, the effects of hopping anisotropy and Hubbard interaction U on the boundaries of the two transitions are observed in detail. The completed phase diagram of the dimerized Kane-Mele-Hubbard model is also obtained in this work. Quantum fluctuations have extremely important influences on a quantum system. However, investigations are under the framework of mean field treatment in this work and the effects of fluctuations in this model will be discussed in the future.
采用解析方法研究了具有/不具有强相互作用的二聚化凯恩 - 梅勒模型。得到了无强相互作用模型的拓扑相变边界。我们的结果表明，相变的发生仅取决于二聚化参数[公式：见正文]。从单粒子能谱出发，我们得到了包含量子自旋霍尔态和拓扑平凡绝缘体的完整相图。然后，使用不同的平均场方法，我们研究了强关联二聚化凯恩 - 梅勒模型的莫特相变和磁相变。在这两个相变之间的区域，具有莫特绝缘体和拓扑相特征的拓扑莫特绝缘体可能是最有趣的相。在这项工作中，详细观察了跳跃各向异性和哈伯德相互作用U对这两个相变边界的影响。这项工作还得到了二聚化凯恩 - 梅勒 - 哈伯德模型的完整相图。量子涨落对量子系统有极其重要的影响。然而，这项工作是在平均场处理的框架下进行的，该模型中涨落的影响将在未来进行讨论。
