Probing the breakdown of topological protection: Filling-factor-dependent evolution of robust quantum Hall incompressible phases
Probing the breakdown of topological protection: Filling-factor-dependent evolution of robust quantum Hall incompressible phases
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DOI：
10.1103/physrevresearch.2.013128
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发表时间：
2020-02-05
影响因子：
4.2
通讯作者：
Hirayama，Y.
中科院分区：
文献类型：
--
作者：
Tomimatsu，T.;Hashimoto，K.;Hirayama，Y.
整数量子霍尔（QH）效应的特点是拓扑量子化和非耗散输运是由一个电绝缘的不可压缩相，防止手性金属通道之间的背散射。我们探讨了不可压缩的区域容易发生故障的拓扑保护使用扫描门技术结合非平衡运输。所得到的图案显示填充因子（-）依赖的演变的微观不可压缩结构位于沿着的边缘和散装区域。我们发现，这些特定的结构，分别归因于不可压缩的边缘带和散装本地化，表现出良好的协议，在依赖的演化与平衡QH不可压缩相的计算，表明非平衡条件下的QH不可压缩相的鲁棒性。此外，我们发现，不可压缩模式的依赖性，反过来，被破坏的大施加电流在深QH效应击穿。这些结果表明，我们的方法的能力，图像的微观输运性质的拓扑二维系统。
The integer quantum Hall (QH) effects characterized by topologically quantized and nondissipative transport are caused by an electrically insulating incompressible phase that prevents backscattering between chiral metallic channels. We probed the incompressible area susceptible to the breakdown of topological protection using a scanning-gate technique incorporating nonequilibrium transport. The obtained pattern revealed the filling-factor- (-) dependent evolution of the microscopic incompressible structures located along the edge and in the bulk region. We found that these specific structures, respectively, attributed to the incompressible edge strip and bulk localization, show good agreement in terms of-dependent evolution with a calculation of the equilibrium QH incompressible phases, indicating the robustness of the QH incompressible phases under the nonequilibrium condition. Further, we found that thedependency of the incompressible patterns is, in turn, destroyed by a large imposed current during the deep QH effect breakdown. These results demonstrate the ability of our method to image the microscopic transport properties of a topological two-dimensional system.