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arXiv · 2505.04726

Quantum geometry and magnon Hall transport in an altermagnet

Erlend Syljuåsen·Alireza Qaiumzadeh·Asle Sudbø
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Abstract

We compute magnon Hall conductivities in a minimal model of a two-dimensional altermagnet. To do so, we derive an analytic expression for the relevant quantum geometric tensor describing two-band bosonic Bogoliubov Hamiltonians, providing insight into the geometric, topological, and transport properties. The magnon thermal Hall and spin Nernst conductivities are shown to directly depend on the altermagnetic parameter, which may serve as an experimental probe of altermagnetism.

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Erlend Syljuåsen, Alireza Qaiumzadeh, Asle Sudbø. 2025-05-07. Quantum geometry and magnon Hall transport in an altermagnet. https://doi.org/10.1103/krk8-655j

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