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arXiv · 1602.04022

Spin-thermoelectric transport induced by interactions and spin-flip processes in two dimensional topological insulators

Flavio Ronetti·Luca Vannucci·Giacomo Dolcetto·Matteo Carrega·Maura Sassetti
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Abstract

We consider thermoelectric transport properties of the edge states of a two dimensional topological insulator in a double quantum point contact geometry coupled to two thermally biased reservoirs. Both spin-preserving and spin-flipping tunneling processes between opposite edges are analyzed in the presence of electron-electron interactions. We demonstrate that the simultaneous presence of spin-flipping processes and interactions gives rise to a finite longitudinal spin current. Moreover, its sign and amplitude can be tuned by means of gate voltages with the possibility to generate a pure spin current, with a vanishing charge current.

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Flavio Ronetti, Luca Vannucci, Giacomo Dolcetto, Matteo Carrega, Maura Sassetti. 2016-02-12. Spin-thermoelectric transport induced by interactions and spin-flip processes in two dimensional topological insulators. https://doi.org/10.1103/physrevb.93.165414

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