论文标题
表面障碍对三维量子厅系统手性表面状态的影响
Effect of surface disorder on the chiral surface states of a three-dimensional quantum Hall system
论文作者
论文摘要
我们研究了表面障碍对三维量子厅系统手性表面状态的影响。利用转移矩阵方法，我们发现沿磁场的表面状态的定位长度随弱障碍制度的表面疾病强度而降低，但在强障碍状态下异常增加。在强大的障碍状态下，表面状态主要定位在第一个内层，以避免最大层的强障碍。可以通过有效的模型来解释定位长度的异常增加，该模型将表面层的强障碍映射到第一个内层的弱混乱症。我们的工作表明，表面障碍可以是控制沿磁场表面状态的运输行为的有效方法。我们还研究了表面障碍对各种表面疾病强度的准二维（1D）状态中表面状态的全部电导p（g）的影响。特别是，我们发现p（g）在准1D金属状态下是高斯，在准1D绝缘体方面是高斯。在跨界方案中，p（g）表现出高度非平凡的形式，其形状与从多弱无序的准准1D线的Dorokhov-mello-pereyra-kumar方程中获得的结果一致，在没有时间逆向对称性的情况下。我们的结果表明，与单参数缩放假设一致，P（g）完全由平均电导率（与系统的细节无关）确定。
We investigate the effect of surface disorder on the chiral surface states of a three-dimensional quantum Hall system. Utilizing a transfer-matrix method, we find that the localization length of the surface state along the magnetic field decreases with the surface disorder strength in the weak disorder regime, but increases anomalously in the strong disorder regime. In the strong disorder regime, the surface states mainly locate at the first inward layer to avoid the strong disorder in the outmost layer. The anomalous increase of the localization length can be explained by an effective model, which maps the strong disorder on the surface layer to the weak disorder on the first inward layer. Our work demonstrates that surface disorder can be an effective way to control the transport behavior of the surface states along the magnetic field. We also investigate the effect of surface disorder on the full distribution of conductances P(g) of the surface states in the quasi-one-dimensional (1D) regime for various surface disorder strengths. In particular, we find that P(g) is Gaussian in the quasi-1D metal regime and log-normal in the quasi-1D insulator regime. In the crossover regime, P(g) exhibits highly nontrivial forms, whose shapes coincide with the results obtained from the Dorokhov-Mello-Pereyra-Kumar equation of a weakly disordered quasi-1D wire in the absence of time-reversal symmetry. Our results suggest that P(g) is fully determined by the average conductance, independent of the details of the system, in agreement with the single-parameter scaling hypothesis.
