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arXiv · 1502.06697

Influence of etching processes on electronic transport in mesoscopic InAs/GaSb quantum well devices

Atindra Nath Pal·Susanne Mueller·Thomas Ihn·Klaus Ensslin·Thomas Tschirky·Christophe Charpentier·Werner Wegscheider
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Abstract

We report the electronic characterization of mesoscopic Hall bar devices fabricated from coupled InAs/GaSb quantum wells sandwiched between AlSb barriers, an emerging candidate for two-dimensional topological insulators. The electronic width of the etched structures was determined from the low field magneto-resistance peak, a characteristic signature of partially diffusive boundary scattering in the ballistic limit. In case of dry-etching the electronic width was found to decrease with electron density. In contrast, for wet etched devices it stayed constant with density. Moreover, the boundary scattering was found to be more specular for wet-etched devices, which may be relevant for studying topological edge states.

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Atindra Nath Pal, Susanne Mueller, Thomas Ihn, Klaus Ensslin, Thomas Tschirky, Christophe Charpentier, Werner Wegscheider. 2015-07-03. Influence of etching processes on electronic transport in mesoscopic InAs/GaSb quantum well devices. https://doi.org/10.1063/1.4926385

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