论文标题
弱拓扑绝缘子中的自旋质地：散装状态和带弯曲的作用
Spin texture in weak topological insulators: the role of bulk states and band bending
论文作者
论文摘要
我们通过超对称方法得出弱拓扑绝缘子的自旋纹理，其中包括散装间隙边缘状态和表面带弯曲的作用。我们发现自旋纹理可以采用四种形式之一：（i）螺旋形，（ii）双曲线，（iii）刺猬，旋转正常为表面状态的狄拉克 - 韦尔锥，以及（iv）双曲线刺猬。在螺旋纹理的情况下，带弯曲决定了绕组数，并且对于所有纹理都可以将自旋纹理极化调整为零。对于弱拓扑绝缘子SNTE，我们表明，包含带弯曲对于获得（111）表面$γ$ -point Dirac-Weyl锥的正确纹理绕组至关重要。我们认为只有在低对称情况下才能找到刺猬。
We derive the spin texture of a weak topological insulator via a supersymmetric approach that includes the roles of the bulk gap edge states and surface band bending. We find the spin texture can take one of four forms: (i) helical, (ii) hyperbolic, (iii) hedgehog, with spins normal to the Dirac-Weyl cone of the surface state, and (iv) hyperbolic hedgehog. Band bending determines the winding number in the case of a helical texture, and for all textures can be used to tune the spin texture polarization to zero. For the weak topological insulator SnTe, we show that inclusion of band bending is crucial to obtain the correct texture winding number for the (111) surface facet $Γ$-point Dirac-Weyl cone. We argue that hedgehogs will be found only in low symmetry situations.
