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arXiv · 1307.6418

Domain Wall Motion in Thin-Film Magnets/ Topological Insulator Junctions

Yago Ferreiros·Alberto Cortijo
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Abstract

We derive the equations of motion of a Domain Wall in a thin-film magnet coupled to the surface states of a Topological Insulator in the presence of of both an electric field along the Domain Wall and a magnetic field perpendicular to the junction. We show how the electric field acts as a chirality stabilizer holding off the appearance of Walker breakdown and enhancing the terminal velocity. We also propose a mechanism to reverse the Domain Wall chirality in a controllable manner by tuning the chiral current flowing through the Wall. An input from a weak perpendicular magnetic field is required in order to break the reflection symmetry that protects the degeneracy of the chirality vacuum.

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Yago Ferreiros, Alberto Cortijo. 2013-07-24. Domain Wall Motion in Thin-Film Magnets/ Topological Insulator Junctions. https://doi.org/10.1103/physrevb.89.024413

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