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Anisotropic resistance with a 90° twist in a ferromagnetic Weyl semimetal, Co₂MnGa.

ABSTRACT: Weyl semimetals exhibit exotic magnetotransport phenomena such as the chiral anomaly and surface-to-bulk quantum oscillations (Weyl orbits) due to chiral bulk states and topologically protected surface states. Here we report a unique transport property in crystals of the ferromagnetic nodal-line Weyl semimetal Co₂MnGa that have been polished to micron thicknesses using a focused ion beam. These thin crystals exhibit a large planar resistance anisotropy (10 × ) with axes that rotate by 90 degrees between opposite faces of the crystal. We use symmetry arguments and electrostatic simulations to show that the observed anisotropy resembles that of an isotropic conductor with surface states that are impeded from hybridization with bulk states. The origin of these states awaits further experiments that can correlate the surface bands with the observed 90° twist.

SUBMITTER: Quirk NP

PROVIDER: S-EPMC10584932 | biostudies-literature | 2023 Oct

REPOSITORIES: biostudies-literature

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Anisotropic resistance with a 90° twist in a ferromagnetic Weyl semimetal, Co2MnGa.

Quirk Nicholas P NP Cheng Guangming G Manna Kaustuv K Felser Claudia C Yao Nan N Ong N P NP

Nature communications 20231018 1

Weyl semimetals exhibit exotic magnetotransport phenomena such as the chiral anomaly and surface-to-bulk quantum oscillations (Weyl orbits) due to chiral bulk states and topologically protected surface states. Here we report a unique transport property in crystals of the ferromagnetic nodal-line Weyl semimetal Co2MnGa that have been polished to micron thicknesses using a focused ion beam. These thin crystals exhibit a large planar resistance anisotropy (10 × ) with axes that rotate by ...[more]

PMID: 37852969

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