Edge transport in the trivial phase of InAs/GaSb
Edge transport in the trivial phase of InAs/GaSb
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DOI：
10.1088/1367-2630/18/8/083005
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发表时间：
2016-07-28
影响因子：
3.3
通讯作者：
Moler, Kathryn A.
中科院分区：
文献类型：
--
作者：
Nichele, Fabrizio;Suominen, Henri J.;Moler, Kathryn A.
我们测量了InAs/GaSb双量子阱的输运和扫描SQUID，该系统被认为是一个二维的拓扑绝缘体。顶门和后门允许独立控制密度和频带偏移，允许从微不足道的微调到拓扑制度。在平凡区域，体传导性被猝灭，但沿边缘的输运持续，表面上类似于在拓扑区域中预测的螺旋边缘通道。我们在各种各样的样品几何形状和测量配置中表征了作为温度、磁场和边缘长度的函数的平凡区域中的边缘传导。尽管与声称测量螺旋边缘通道的研究有相似之处，但我们的表征指向这些观测的非拓扑源。
Wepresent transport and scanning SQUID measurements on InAs/GaSb double quantum wells, a system predicted to be a two-dimensional topological insulator. Top and back gates allow independent control of density and band offset, allowing tuning from the trivial to the topological regime. In the trivial regime, bulk conductivity is quenched but transport persists along the edges, superficially resembling the predicted helical edge-channels in the topological regime. Wecharacterize edge conduction in the trivial regime in a wide variety of sample geometries and measurement configurations, as a function of temperature, magnetic field, and edge length. Despite similarities to studies claiming measurements of helical edge channels, our characterization points to a non-topological origin for these observations.