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arXiv · 2608.26260

Hidden Frustration in Collinear Altermagnets: Pairing Vortices and Equilibrium Spin Current Loops

Vincent P. Flynn·Benedetta Flebus
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Abstract

We show that a magnet can remain perfectly collinear while its quantum vacuum circulates. In a centrosymmetric altermagnet, a symmetry-allowed locally staggered Dzyaloshinskii-Moriya coupling imprints a gauge-irremovable vortex-antivortex pair into the anomalous magnon pair correlations at high-symmetry points in momentum space. In real space, these hidden vortices produce an antiferrochiral array of equilibrium spin currents circulating oppositely around neighboring plaquettes. Gauge-irremovable frustration therefore survives despite classical collinearity: it exists entirely in the quantum correlations. Our results show that complex pairing, gauge-invariant fluxes, and equilibrium loop currents - structures encountered across electronic flux phases, spin liquids, and frustrated quantum magnets - can be encoded in the squeezed vacuum of a collinear magnet.

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Vincent P. Flynn, Benedetta Flebus. 2026-08-26. Hidden Frustration in Collinear Altermagnets: Pairing Vortices and Equilibrium Spin Current Loops. https://arxiv.org/abs/2608.26260

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