论文标题
模型量子旋转厅绝缘子中的激子拓扑和凝结
Exciton topology and condensation in a model quantum spin Hall insulator
论文作者
论文摘要
我们通过一致的平均场方案进行研究，在Bernevig，Hughes和Zhang模型的量子自旋霍尔绝缘子中，局部电子电子排斥的单粒子特性的作用。我们发现，这种相互作用促进了新的绝缘和磁性阶段的拓扑和非探针绝缘体之间的侵入，从而破坏了自发的反转和时间逆转对称性，而不是它们的产物。从拓扑结构和非本质方面来到这一阶段的方法是通过两个激子分支的软化来信号，即，在大多数情况下，其结合能达到了间隙值，在大多数情况下，它具有有限的和相反的Chern数字，从而允许该阶段被视为拓扑激素的冷凝物。我们还讨论了这些激子，尤其是它们的表面如何影响物理可观察物。
We study by a consistent mean-field scheme the role on the single- and two-particle properties of a local electron-electron repulsion in the Bernevig, Hughes and Zhang model of a quantum spin Hall insulator. We find that the interaction fosters the intrusion between the topological and non-topological insulators of a new insulating and magnetoelectric phase that breaks spontaneously inversion and time reversal symmetries, but not their product. The approach to this phase from both topological and non-topological sides is signalled by the softening of two exciton branches, i.e., whose binding energy reaches the gap value, that possess, in most cases, finite and opposite Chern numbers, thus allowing this phase being regarded as a condensate of topological excitons. We also discuss how those excitons, and especially their surface counterparts, may influence the physical observables.
