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Gigantic tunneling magnetoresistance in magnetic Weyl semimetal tunnel junctions.

ABSTRACT: We investigate the tunneling magnetoresistance in magnetic tunnel junctions (MTJs) comprised of Weyl semimetal contacts. We show that chirality-magnetization locking leads to a gigantic tunneling magnetoresistance ratio, an effect that does not rely on spin filtering by the tunnel barrier. Our results indicate that the conductance in the anti-parallel configuration is more sensitive to magnetization fluctations than in MTJs with normal ferromagnets, and predicts a TMR as large as 10⁴ % when realistic magnetization fluctuations are accounted for. In addition, we show that the Fermi arc states give rise to a non-monotonic dependence of conductance on the misalignment angle between the magnetizations of the two contacts.

SUBMITTER: de Sousa DJP

PROVIDER: S-EPMC9982938 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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Gigantic tunneling magnetoresistance in magnetic Weyl semimetal tunnel junctions.

de Sousa D J P DJP Ascencio C O CO Haney P M PM Wang J P JP Low Tony T

Physical review. B 20210701 4

We investigate the tunneling magnetoresistance in magnetic tunnel junctions (MTJs) comprised of Weyl semimetal contacts. We show that chirality-magnetization locking leads to a gigantic tunneling magnetoresistance ratio, an effect that does not rely on spin filtering by the tunnel barrier. Our results indicate that the conductance in the anti-parallel configuration is more sensitive to magnetization fluctations than in MTJs with normal ferromagnets, and predicts a TMR as large as 10<sup>4</sup> ...[more]

PMID: 36875244

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