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arXiv · 1908.08680

Momentum-Dependent Spin Splitting by Collinear Antiferromagnetic Ordering

Satoru Hayami·Yuki Yanagi·Hiroaki Kusunose
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Abstract

We clarify the macroscopic symmetry and microscopic model-parameter conditions for emergence of spin-split electronic band structure in collinear antiferromagnets without atomic spin-orbit coupling. By using the microscopic multipole descriptions, we elucidate the fundamental degree of freedom in a cluster unit of an antiferromagnet giving rise to an effective spin-orbit interaction through the anisotropic kinetic motions of electrons. We show a correspondence of the ordering patterns and resultant momentum-dependent spin splitting for 32 crystallographic point groups after demonstrating two intuitive examples of four-sublattice pyrochlore and tetragonal systems. Our study unveils potential features of collinear antiferromagnets with considerably weak spin-orbit coupling in light-element materials and 3$d$ transition metal oxides, which can be utilized for a spin-current generation by electric (thermal) current and a magneto-striction effect.

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Satoru Hayami, Yuki Yanagi, Hiroaki Kusunose. 2019-08-23. Momentum-Dependent Spin Splitting by Collinear Antiferromagnetic Ordering. https://doi.org/10.7566/jpsj.88.123702

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