标题： 无序轴子绝缘体中分离的表面和体态拓扑安德森局域化相变 显示英文标题

标题： Separate surface and bulk topological Anderson localization transitions in disordered axion insulators

摘要： 在体和边界支持不同电子能隙的物质拓扑相中，存在在无序存在下解耦的迁移率能隙的可能性。 这类似于在传统朗道理论中实现独立或伴随的体-边界临界性的广泛研究问题。 使用具有清洁、带隙表面且具有$e^2/2h$量化霍尔电导率的三维轴子绝缘体，我们展示了在无序存在下，体和表面迁移率能隙演化方式不同。 体和表面拓扑的解耦产生了一个实现二维、非量化异常霍尔金属的区域，该区域属于高斯酉系综（GUE），其一些光谱和响应特性与传统三维（3D）拓扑绝缘体的表面态相似。 讨论了这些结果的普遍性以及对其他绝缘体和超导体的扩展。 显示英文摘要

摘要： In topological phases of matter for which the bulk and boundary support distinct electronic gaps, there exists the possibility of decoupled mobility gaps in the presence of disorder. This is in analogy with the well-studied problem of realizing separate or concomitant bulk-boundary criticality in conventional Landau theory. Using a three-dimensional axion insulator having clean, gapped surfaces with $e^2/2h$ quantized Hall conductance, we show the bulk and surface mobility gap evolve differently in the presence of disorder. The decoupling of the bulk and surface topology yields a regime that realizes a two-dimensional, unquantized anomalous Hall metal in the Gaussian unitary ensemble (GUE), which shares some spectral and response properties akin to the surface states of a conventional three-dimensional (3D) topological insulator. The generality of these results as well as extensions to other insulators and superconductors is discussed.