论文标题
拓扑绝缘子表面上的Moiré超级晶格
A moiré superlattice on the surface of a topological insulator
论文作者
论文摘要
扭曲的范德华异质结构以诱导相关的多体状态提供了一种新型的调整机制，以固态物理学。在这项工作中，我们从理论上研究了具有超晶格电位的三维拓扑绝缘子的表面狄拉克锥的命运。使用图解摄动理论，晶格模型模拟和从头算的结合，我们阐明了具有诱导的Moiré电位的单个Dirac锥体的独特方面，以及散装拓扑在重建的表面带结构中的作用。我们报告了表面狄拉克锥速度的戏剧性重新归一化，并证明了对孤立小型班的形成的拓扑障碍。由于散装的拓扑性质，表面带隙无法打开。取而代之的是，出现了额外的卫星狄拉克锥体，可以是高度各向异性的，并使其变得平坦。我们讨论了我们发现对未来实验的含义。
Twisting van der Waals heterostructures to induce correlated many-body states provides a novel tuning mechanism in solid-state physics. In this work, we theoretically investigate the fate of the surface Dirac cone of a three-dimensional topological insulator subject to a superlattice potential. Using a combination of diagrammatic perturbation theory, lattice model simulations, and ab initio calculations we elucidate the unique aspects of twisting a single Dirac cone with an induced moiré potential and the role of the bulk topology on the reconstructed surface band structure. We report a dramatic renormalization of the surface Dirac cone velocity as well as demonstrate a topological obstruction to the formation of isolated minibands. Due to the topological nature of the bulk, surface band gaps cannot open; instead, additional satellite Dirac cones emerge, which can be highly anisotropic and made quite flat. We discuss the implications of our findings for future experiments.
