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arXiv · 1401.1531

Images of edge current in InAs/GaSb quantum wells

Eric M. Spanton·Katja C. Nowack·Lingjie Du·Gerard Sullivan·Rui-Rui Du·Kathryn A. Moler
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Abstract

Quantum spin Hall devices with edges much longer than several microns do not display ballistic transport: that is, their measured conductances are much less than $e^2/h$ per edge. We imaged edge currents in InAs/GaSb quantum wells with long edges and determined an effective edge resistance. Surprisingly, although the effective edge resistance is much greater than $h/e^2$, it is independent of temperature up to 30 K within experimental resolution. Known candidate scattering mechanisms do not explain our observation of an effective edge resistance that is large yet temperature-independent.

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Eric M. Spanton, Katja C. Nowack, Lingjie Du, Gerard Sullivan, Rui-Rui Du, Kathryn A. Moler. 2014-06-21. Images of edge current in InAs/GaSb quantum wells. https://doi.org/10.1103/physrevlett.113.026804

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