论文标题
扭曲的双层石墨烯中对称性断裂相关阶段的层次结构
Hierarchy of Symmetry Breaking Correlated Phases in Twisted Bilayer Graphene
论文作者
论文摘要
$ \ sim1.1.1^{o} $附近的扭曲双层石墨烯(TBG)显示了丰富的相图。但是,不同阶段之间的相互作用及其对扭角的依赖仍然难以捉摸。在这里,我们探讨了各种TBG相的稳定性,并证明,在费米表面的重建以及熵驱动的高温相变和线性的高温相变和线性抗性的扭曲角度在远远超出了这些偏远的相关式隔热阶段的范围内。在魔术角附近,我们还找到了一个金属相,该阶段显示出滞后异常的霍尔效应和初期的Chern绝缘行为。这样的金属相可以根据导致浆果曲率重新分布和费米表面重建的TBG带的相互作用变形之间的相互作用来合理化。我们的结果提供了关于TBG相关阶段层次结构的广泛观点,这些阶段是由于它们的稳健性抵抗魔法角度的偏差,或者等效地是其电子相互作用要求。
Twisted bilayer graphene (TBG) near the magic twist angle of $\sim1.1^{o}$ exhibits a rich phase diagram. However, the interplay between different phases and their dependence on twist angle is still elusive. Here, we explore the stability of various TBG phases and demonstrate that superconductivity near filling of two electrons per moiré unit cell alongside Fermi surface reconstructions, as well as entropy-driven high-temperature phase transitions and linear-in-T resistance occur over a range of twist angles which extends far beyond those exhibiting correlated insulating phases. In the vicinity of the magic angle, we also find a metallic phase that displays a hysteretic anomalous Hall effect and incipient Chern insulating behaviour. Such a metallic phase can be rationalized in terms of the interplay between interaction-driven deformations of TBG bands leading to Berry curvature redistribution and Fermi surface reconstruction. Our results provide an extensive perspective on the hierarchy of correlated phases in TBG as classified by their robustness against deviations from the magic angle or, equivalently, their electronic interaction requirements.