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arXiv · 2410.01689

Neel vector dependent orbital Hall effect in altermagnetic RuO2

Yuta Yahagi
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Abstract

Orbital Hall effect in the altermagnetic RuO2 is theoretically investigated. Transport calculations using the Kubo formula with a first-principles tight-binding model present a significant orbital Hall conductivity depending on the direction of the Neel vector. An pertuabative analysis explaines the mechanism by two roles of the spin-orbit interaction: converting the spin current into the parallelly polarized orbital current; recovering the orbital angular momentum anisotropically under the orthorhombic ligand field on the Ru sites. From an application perspective, this effect provides a promising method of generating orbital currents polarizing to arbitrary directions, realising an orbital source offering both controllability and efficiency.

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Yuta Yahagi. 2024-10-02. Neel vector dependent orbital Hall effect in altermagnetic RuO2. https://arxiv.org/abs/2410.01689

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