Helicity-protected domain-wall magnetoresistance in ferromagnetic Weyl semimetal

Koji Kobayashi; Yuya Ominato; Kentaro Nomura

doi:10.7566/jpsj.87.073707

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arXiv · 1802.04536

Helicity-protected domain-wall magnetoresistance in ferromagnetic Weyl semimetal

Koji Kobayashi·Yuya Ominato·Kentaro Nomura

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Abstract

The magnetotransport properties of disordered ferromagnetic Weyl semimetals are investigated numerically. We found an extraordinarily stable and huge magnetoresistance effect in domain walls of Weyl semimetals. This effect originates from the helicity mismatch of Weyl fermions and is a specific property of Weyl semimetals. Although conventional magnetoresistance effects are strongly suppressed in domain walls where local magnetization varies gradually, the helicity-protected magnetoresistance in Weyl semimetals maintains almost $100\%$ of the magnetoresistance ratio for any kind of thick domain walls, even in the presence of disorder. The contribution of surface Fermi arcs to the magnetoresistance is also discussed.

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Koji Kobayashi, Yuya Ominato, Kentaro Nomura. 2018-02-13. Helicity-protected domain-wall magnetoresistance in ferromagnetic Weyl semimetal. https://doi.org/10.7566/jpsj.87.073707

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