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arXiv · 2204.07326

Spin Conductivity Based on Magnetic Toroidal Quadrupole Hidden in Antiferromagnets

Satoru Hayami·Megumi Yatsushiro
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Abstract

We report our theoretical results on spin conductivity in antiferromagnets by focusing on the role of the magnetic toroidal quadrupole (MTQ) in electron systems. The MTQ is characterized as a time-reversal-odd rank-2 polar tensor degree of freedom in electrons, which is distinct from conventional rank-1 magnetic and magnetic toroidal dipoles. Based on a microscopic $sd$ model analysis for a tetragonal system under both collinear and noncollinear antiferromagnetic orderings, we clarify that the MTQ becomes a source of an extrinsic spin conductivity even with neither a uniform magnetization nor spin-orbit coupling. We also list all the magnetic point groups to accommodate the MTQs as a primary order parameter as well as the candidate antiferromagnetic materials.

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Satoru Hayami, Megumi Yatsushiro. 2022-04-15. Spin Conductivity Based on Magnetic Toroidal Quadrupole Hidden in Antiferromagnets. https://doi.org/10.7566/jpsj.91.063702

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