1. Large inverted band-gap in strained three-layer InAs/GaInSb quantum wells
- Author
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Avogadri, C., Gebert, S., Krishtopenko, S. S., Castillo, I., Consejo, C., Ruffenach, S., Roblin, C., Bray, C., Krupko, Y., Juillaguet, S., Contreras, S., Wolf, A., Hartmann, F., Höfling, S., Boissier, G., Rodriguez, J. B., Nanot, S., Tournié, E., Teppe, F., and Jouault, B.
- Subjects
Condensed Matter - Mesoscale and Nanoscale Physics - Abstract
Quantum spin Hall insulators (QSHIs) based on HgTe and three-layer InAs/GaSb quantum wells (QWs) have comparable bulk band-gaps of about 10--18~meV. The former however features a band-gap vanishing with temperature, while the gap in InAs/GaSb QSHIs is rather temperature-independent.Here, we report on the realization of large inverted band-gap in strained three-layer InAs/GaInSb QWs. By temperature-dependent magnetotransport measurements of gated Hall bar devices, we extract a gap as high as 45 meV. Combining local and non-local measurements, we attribute the edge conductivity observed at temperatures up to 40 K to the topological edge channels with equilibration lengths of a few micrometers. Our findings pave the way toward manipulating edge transport at high temperatures in QW heterostructures.
- Published
- 2022