arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1302.3014cond-mat.mes-hall
收藏

通过无序拓扑金属带的输运

Transport through a disordered topological-metal strip

Alexandra Junck, Kun W. Kim, Doron L. Bergman, T. Pereg-Barnea, Gil Refael

摘要:

拓扑相位的特征,特别是边缘状态,可能会被与平凡导带的能量重叠所掩盖。这种导体的拓扑性质,然而,揭示在其输运性质,特别是在存在的障碍。在这项工作中,我们探讨了这样一个系统的无序存在的电导行为,并与一个理想的二维拓扑绝缘体的量子化电导进行对比。我们的分析依赖于格子系统上的数值和简单玩具模型上的分析。有趣的是,我们发现,随着无序度从零开始增加,边缘电导率最初从其量化值下降;然而,随着无序度继续增加,电导率恢复,并在略低于干净系统的量化值的值处饱和。我们讨论了如何可以理解这种效果的倾向,体状态本地化,而边缘状态保持离域。

英文摘要:

Features of a topological phase, and edge states in particular, may be obscured by overlapping in energy with a trivial conduction band. The topological nature of such a conductor, however, is revealed in its transport properties, especially in the presence of disorder. In this work, we explore the conductance behavior of such a system with disorder present, and contrast it with the quantized conductance in an ideal 2D topological insulator. Our analysis relies on numerics on a lattice system and analytics on a simple toy model. Interestingly, we find that as disorder is increased from zero, the edge conductivity initially falls from its quantized value; yet as disorder continues to increase, the conductivity recovers, and saturates at a value slightly below the quantized value of the clean system. We discuss how this effect can be understood from the tendency of the bulk states to localize, while the edge states remain delocalized.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑