论文标题
增强和稳定的自旋霍尔电导率，无序的时间反转和反转对称性破碎的拓扑绝缘膜薄膜
Enhanced and stable spin Hall conductivity in a disordered time-reversal and inversion symmetry broken topological insulator thin film
论文作者
论文摘要
我们认为将无序的拓扑绝缘膜薄膜放在带有垂直交换场$ m $的铁磁绝缘子顶部，并经历垂直电场。铁磁绝缘子的存在导致拓扑绝缘子薄膜的底部表面状态变为旋转极化，并且电场在两个表面状态之间提供了潜在的差异$ v $，从而导致系统中的时间反向和反转对称破坏。我们使用久保形式主义并采用了第一个诞生的近似以及自洽天生的近似，我们计算了旋转厅的电导率。我们发现，对于$ v $的小值，可以通过距电荷中立点的$ M $远的大量值生成大型自旋电导率。但是，对于$ v $的巨大值，即使在充电中性点附近，旋转电导率也可以促进。还检查了顶点校正的作用和对疾病的大型自旋电导率的稳定性。
We consider a disordered topological insulator thin film placed on the top of a ferromagnetic insulator with a perpendicular exchange field $M$ and subjected to a perpendicular electric field. The presence of ferromagnetic insulator causes that bottom surface states of the topological insulator thin film become spin polarized and the electric field provides a potential difference $V$ between the two surface states, resulting in breaking of time-reversal and inversion symmetry in the system. Using Kubo formalism and employing the first Born approximation as well as the self-consistent Born approximation, we calculate the spin Hall conductivity. We find that for small values of $V$, a large spin conductivity can be generated through large values of $M$ away from the charge neutrality point. But for large values of $V$, the spin conductivity can be promoted even with small values of $M$ around the charge neutrality point. The effect of vertex corrections and the stability of the obtained large spin conductivity against disorders are also examined.
