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arXiv · 1003.2008

Magnetoelectric Response of the Time-Reversal Invariant Helical Metal

Ion Garate·M. Franz
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Abstract

We derive compact analytical expressions for the coupled spin-charge susceptibility of a clean helical metal at the surface of a three dimensional topological insulator (TI). These expressions lead to unconventional non-collinear RKKY interactions between two impurity magnetic moments placed on the surface of a TI, and predict the generation of electric currents by time-dependent magnetic moments. We determine the influence of gate and bias voltages on the interlayer exchange coupling between two single-domain ferromagnetic monolayers deposited on top of a TI.

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Ion Garate, M. Franz. 2010-03-10. Magnetoelectric Response of the Time-Reversal Invariant Helical Metal. https://doi.org/10.1103/physrevb.81.172408

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