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arXiv · 1610.08107

Electric control of Dirac quasiparticles by spin-orbit torque in an antiferromagnet

Libor Šmejkal·Jakub Železný·Jairo Sinova·Tomáš Jungwirth
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Abstract

Spin-orbitronics and Dirac quasiparticles are two fields of condensed matter physics initiated independently about a decade ago. Here we predict that Dirac quasiparticles can be controlled by the spin-orbit torque reorientation of the Néel vector in an antiferromagnet. Using CuMnAs as an example, we formulate symmetry criteria allowing for the co-existence of Dirac quasiparticles and Néel spin-orbit torques. We identify the non-symmorphic crystal symmetry protection of Dirac band crossings whose on and off switching is mediated by the Néel vector reorientation. We predict that this concept, verified by minimal model and density functional calculations in the CuMnAs semimetal antiferromagnet, can lead to a topological metal-insulator transition driven by the Néel vector and to the corresponding topological anisotropic magnetoresistance.

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Libor Šmejkal, Jakub Železný, Jairo Sinova, Tomáš Jungwirth. 2016-10-25. Electric control of Dirac quasiparticles by spin-orbit torque in an antiferromagnet. https://doi.org/10.1103/physrevlett.118.106402

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