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arXiv · 1209.3634

Spin current pumping in helical Luttinger liquids

Dario Ferraro·Giacomo Dolcetto·Roberta Citro·Francesco Romeo·Maura Sassetti
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Abstract

We study the DC spin current induced into an unbiased quantum spin Hall system through a two-point contacts setup with time dependent electron tunneling amplitudes. By means of two external gates, it is possible to drive a current with spin-preserving and spin-flipping contributions showing peculiar oscillations as a function of pumping frequency, electron-electron interaction and temperature. From its interference patterns as a function of the Fabry-Perot and Aharonov-Bohm phases, it is possible to extract information about the helical nature of the edge states and the intensity of the electron-electron interaction.

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Dario Ferraro, Giacomo Dolcetto, Roberta Citro, Francesco Romeo, Maura Sassetti. 2012-09-17. Spin current pumping in helical Luttinger liquids. https://doi.org/10.1103/physrevb.87.245419

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