论文标题
TA2NISE5：具有多个频段反转的候选拓扑激素绝缘子
Ta2NiSe5: a candidate topological excitonic insulator with multiple band inversions
论文作者
论文摘要
基于密度功能理论，研究了准二维激发型绝缘子TA2Nise5的正晶和单斜相阶段的电子结构和拓扑特性。与先前研究的许多拓扑绝缘子中，在FEMI水平的单个平价或带式反转相反，在TA2NISE5的两个阶段中都有多种奇偶校验和带有旋转轨道耦合的带反转，从而导致更复杂和拓扑上的非拓扑和拓扑上的非平淡无奇的电子结构。还获得了低温单斜相相的狄拉克锥类型表面状态。在本文中，我们证明TA2Nise5是一个有前途的候选人，作为三维拓扑激素绝缘体。
The electronic structures and topological properties of the orthorhombic and monoclinic phases of the quasi-one-dimensional excitonic insulator Ta2NiSe5 are investigated based on density functional theory. In contrast to a single parity or band inversion across the Fermi level in many topological insulators studied previously, there are multiple parity and band inversions with or without spin-orbit coupling in both phases of Ta2NiSe5, resulting in more complex and topologically nontrivial electronic structures. The Dirac cone type surface states of the low-temperature monoclinic phase are also obtained. In this paper, we demonstrate that Ta2NiSe5 is a promising candidate as a three-dimensional topological excitonic insulator.
