标题： 螺旋边缘态在多个拓扑质量区域中 显示英文标题

标题： Helical edge states in multiple topological mass domains

摘要： 二维拓扑绝缘相已在HgTe量子阱(QWs)中被实验发现。 二维拓扑绝缘体(TIs)的低能物理由Bernevig-Hughes-Zhang(BHZ)模型描述，其中拓扑绝缘相或正常绝缘相的实现分别取决于狄拉克质量为负或正。 我们求解了质量区域配置的BHZ模型，分析了正常绝缘区中有限狄拉克质量对边缘模的影响（软壁边界条件）。 我们表明，在TI和正常绝缘体(NI)之间的边界处，出现在界面的边缘态的狄拉克点强烈依赖于两个区域中狄拉克质量的比值。 我们还考虑了多个边界的情况，如NI/TI/NI、TI/NI/TI和NI/TI/NI/TI。 显示英文摘要

摘要： The two-dimensional topological insulating phase has been experimentally discovered in HgTe quantum wells (QWs). The low-energy physics of two-dimensional topological insulators (TIs) is described by the Bernevig-Hughes-Zhang (BHZ) model, where the realization of a topological or a normal insulating phase depends on the Dirac mass being negative or positive, respectively. We solve the BHZ model for a mass domain configuration, analyzing the effects on the edge modes of a finite Dirac mass in the normal insulating region (soft-wall boundary condition). We show that at a boundary between a TI and a normal insulator (NI), the Dirac point of the edge states appearing at the interface strongly depends on the ratio between the Dirac masses in the two regions. We also consider the case of multiple boundaries such as NI/TI/NI, TI/NI/TI and NI/TI/NI/TI.