Absence of cross-sublattice spin pumping and spin-transfer torques in collinear antiferromagnets

Junyu Tang; Ran Cheng

doi:10.1063/5.0159062

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arXiv · 2305.13334

Absence of cross-sublattice spin pumping and spin-transfer torques in collinear antiferromagnets

Junyu Tang·Ran Cheng

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Abstract

We resolve the debate over the existence and magnitude of cross-sublattice (CS) contributions to spin pumping and spin-transfer torques in a two-sublattice antiferromagnet connected to a non-magnetic metal. Guided by symmetry considerations, we first relate the controversial CS terms to specific components in the spin conductance matrix. Then we quantify these components by studying the spin-dependent electron scattering on a fully compensated interface. We ascertain the absence of all CS contributions in the collinear regime. Even in the non-collinear regime, the CS contributions only constitute a higher-order correction to the existing theory.

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Junyu Tang, Ran Cheng. 2023-05-20. Absence of cross-sublattice spin pumping and spin-transfer torques in collinear antiferromagnets. https://doi.org/10.1063/5.0159062

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