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arXiv · 0905.0611

Transport through a band insulator with Rashba spin-orbit coupling: metal-insulator transition and spin-filtering effects

Abstract

We calculate the current-voltage characteristic of a one-dimensional band insulator with magnetic field and Rashba spin-orbit coupling which is connected to nonmagnetic leads. Without spin-orbit coupling we find a complete spin-filtering effect, meaning that the electric transport occurs in one spin channel only. For a large magnetic field which closes the band gap, we show that spin-orbit coupling leads to a transition from metallic to insulating behavior. The oscillations of the different spin-components of the current with the length of the transport channel are studied as well.

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Thibaut Jonckheere, George Japaridze, Thierry Martin, Roland Hayn. 2009-05-05. Transport through a band insulator with Rashba spin-orbit coupling: metal-insulator transition and spin-filtering effects. https://doi.org/10.1103/physrevb.81.165443

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