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arXiv · 2002.07073

Efficient Electrical Spin-Splitter Based on Non-Relativistic Collinear Antiferromagnetism

Rafael González-Hernández·Libor Šmejkal·Karel Výborný·Yuta Yahagi·Jairo Sinova·Tomáš Jungwirth·Jakub Železný
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Abstract

Electrical spin-current generation is among the core phenomena driving the field of spintronics. Using {\em ab initio} calculations we show that a room-temperature metallic collinear antiferromagnet RuO$_2$ allows for highly efficient spin-current generation, arising from anisotropically-split bands with conserved up and down spins along the Néel vector axis. The zero net moment antiferromagnet acts as an electrical spin-splitter with a 34$^\circ$ propagation angle between spin-up and spin-down currents. Correspondingly, the spin-conductivity is a factor of three larger than the record value from a survey of 20,000 non-magnetic spin-Hall materials. We propose a versatile spin-splitter-torque concept utilizing antiferromagnetic RuO$_2$ films interfaced with a ferromagnet.

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Rafael González-Hernández, Libor Šmejkal, Karel Výborný, Yuta Yahagi, Jairo Sinova, Tomáš Jungwirth, Jakub Železný. 2020-08-10. Efficient Electrical Spin-Splitter Based on Non-Relativistic Collinear Antiferromagnetism. https://doi.org/10.1103/physrevlett.126.127701

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