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arXiv · 1902.04436

Antiferromagnetism in RuO$_2$ as $d$-wave Pomeranchuk instability

Kyo-Hoon Ahn·Atsushi Hariki·Kwan-Woo Lee·Jan Kuneš
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Abstract

We present a computational study of antiferromagnetic transition in RuO$_2$. The rutile structure with the magnetic sublattices coupled by $π/2$-rotation leads to a spin-polarized band structure in the antiferromagnetic state, which gives rise to a $d$-wave modulation of the Fermi surface in the spin-triplet channel. We argue a finite spin conductivity that changes sign in the $ab$ plane is expected RuO$_2$ because of this band structure. We analyze the origin of the antiferromagnetic instability and link it to presence of a nodal line close to the Fermi level.

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Kyo-Hoon Ahn, Atsushi Hariki, Kwan-Woo Lee, Jan Kuneš. 2019-02-12. Antiferromagnetism in RuO$_2$ as $d$-wave Pomeranchuk instability. https://doi.org/10.1103/physrevb.99.184432

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