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arXiv · 1604.05546

Transport through a quantum spin Hall antidot as a spectroscopic probe of spin textures

Alexia Rod·Giacomo Dolcetto·Stephan Rachel·Thomas L. Schmidt
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Abstract

We investigate electron transport through an antidot embedded in a narrow strip of two-dimensional topological insulator. We focus on the most generic and experimentally relevant case with broken axial spin symmetry. Spin-non-conservation allows additional scattering processes which change the transport properties profoundly. We start from an analytical model for noninteracting transport, which we also compare with a numerical tight-binding simulation. We then extend this model by including Coulomb repulsion on the antidot, and we study the transport in the Coulomb-blockade limit. We investigate sequential tunneling and cotunneling regimes, and we find that the current-voltage characteristic allows a spectroscopic measurement of the edge-state spin textures.

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Alexia Rod, Giacomo Dolcetto, Stephan Rachel, Thomas L. Schmidt. 2016-04-19. Transport through a quantum spin Hall antidot as a spectroscopic probe of spin textures. https://doi.org/10.1103/physrevb.94.035428

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