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arXiv · 1008.1195

Charge-spin duality in non-equilibrium transport of helical liquids

Chao-Xing Liu·Jan Carl Budich·Patrik Recher·Bjoern Trauzettel
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Abstract

Non-equilibrium transport properties of charge and spin sector of two edges of a quantum spin Hall insulator are investigated theoretically in a four-terminal configuration. A simple duality relation between charge and spin sector is found for two helical Tomonaga Luttinger liquids (hTTLs) connected to non-interacting electron reservoirs. If the hTLLs on opposite edges are coupled locally or non-locally, the mixing between them yields interesting physics where spin information can be easily detected by a charge measurement and vice versa. Particularly, we show how a pure spin density in the absence of charge current can be generated in a setup that contains two hTLL and one spinful Tomonaga Luttinger liquid in between.

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Chao-Xing Liu, Jan Carl Budich, Patrik Recher, Bjoern Trauzettel. 2010-08-06. Charge-spin duality in non-equilibrium transport of helical liquids. https://doi.org/10.1103/physrevb.83.035407

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