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arXiv · 2604.19156

Triple-${\bf Q}$ collinear state with compensated ferrimagnetic nature on frustrated kagome lattice

Kazushi Aoyama·Hikaru Kawamura
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Abstract

Spin-selective band splitting without net magnetization and spin-orbit couplings serves for a next-generation spin-current generator, and its typical platforms are altermagnets and compensated ferrimagnets as well, where the existence of a crystal asymmetry or nonequivalent sites is essential. Here, we theoretically demonstrate that such a splitting can be realized in a triple-{\bf Q} 12-sublattice state emerging in a $J_3$-dominant kagome antiferromagnet, without the help of the crystal asymmetry. Reflecting the multi-sublattice nature, a local magnetization reveals a fully compensated ferrimagnetic pattern in units of a triangle plaquette, leading to $s$-wave-type spin splittings in magnon and electron bands. This enables an atiferromagnetic spin Seebeck effect at zero field in insulating systems and filling-controlled polarized states in metallic systems, highlighting the potential of frustrated magnets to realize novel spintronics functionalities.

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Kazushi Aoyama, Hikaru Kawamura. 2026-04-21. Triple-${\bf Q}$ collinear state with compensated ferrimagnetic nature on frustrated kagome lattice. https://doi.org/10.1038/s44306-026-00147-x

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