Symmetry-allowed nonlinear orbital response across the topological phase transition in centrosymmetric materials
Symmetry-allowed nonlinear orbital response across the topological phase transition in centrosymmetric materials
复制标题
中心对称材料拓扑相变中对称性允许的非线性轨道响应
DOI：
10.1103/physrevb.105.l121407
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发表时间：
2022
影响因子：
3.7
通讯作者：
Ishizuka Hiroaki
中科院分区：
文献类型：
--
作者：
Davydova Margarita;Serbyn Maksym;Ishizuka Hiroaki
非线性光学响应通常用作研究材料电子特性的探针。对于拓扑材料，迄今为止的研究主要集中在光电流上，这在中心对称材料中是被禁止的，因为它们需要破缺的反演对称性。在这封信中，我们提出了一类具有两个双简并能带的反演对称拓扑绝缘体的对称允许响应。我们考虑这种响应的一个具体例子，即轨道电流，并表明响应的符号反映了拓扑指数，即轨道电流在平凡相和拓扑绝缘体相之间的过渡时改变符号。这在拓扑绝缘体的两个模型中得到了说明：Bernevig-Hughes-Zhang 模型和过渡金属二硫属化物相。
Nonlinear optical responses are commonly used as a probe for studying the electronic properties of materials. For topological materials, studies thus far focused on photogalvanic electric currents, which are forbidden in centrosymmetric materials because they require broken inversion symmetry. In this Letter, we propose a class of symmetry-allowed responses for inversion-symmetric topological insulators with two doubly degenerate bands. We consider a specific example of such a response, the orbital current, and show that the sign of the response reflects thetopological index, i.e., the orbital currentchanges signat the transition between trivial and topological insulator phases. This is illustrated in two models of topological insulators: the Bernevig-Hughes-Zhang model and thephase of transition metal dichalcogenides.