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arXiv · 1207.7259

Backscattering Between Helical Edge States via Dynamic Nuclear Polarization

Adrian Del Maestro·Timo Hyart·Bernd Rosenow
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Abstract

We show that that the non-equilibrium spin polarization of one dimensional helical edge states at the boundary of a two dimensional topological insulator can dynamically induce a polarization of nuclei via the hyperfine interaction. When combined with a spatially inhomogeneous Rashba coupling, the steady state polarization of the nuclei produces backscattering between the topologically protected edge states leading to a reduction in the conductance which persists to zero temperature. We study these effects in both short and long edges, uncovering deviations from Ohmic transport at finite temperature and a current noise spectrum which may hold the fingerprints for experimental verification of the backscattering mechanism.

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Adrian Del Maestro, Timo Hyart, Bernd Rosenow. 2012-07-31. Backscattering Between Helical Edge States via Dynamic Nuclear Polarization. https://doi.org/10.1103/physrevb.87.165440

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