Effective interaction quenching in artificial kagom\'e spin chains

L. Salmon; V. Schánilec; J. Coraux; B. Canals; N. Rougemaille

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arXiv · 2310.11933

Effective interaction quenching in artificial kagom\'e spin chains

L. Salmon·V. Schánilec·J. Coraux·B. Canals·N. Rougemaille

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Abstract

Achieving thermal equilibrium in two-dimensional lattices of interacting nanomagnets has been a key issue on the route to study exotic phases in artificial frustrated magnets. We revisit this issue in artificial one-dimensional kagom\'e spin chains. Imaging arrested micro-states generated by a field demagnetization protocol and analyzing their pairwise spin correlations in real space, we unveil a non-equilibrated physics. Remarkably, this physics can be reformulated into an at-equilibrium one by rewriting the associated spin Hamiltonian in such a way that one of the coupling constants is quenched. We ascribe this effective behavior to a kinetic hinderance during the demagnetization protocol, which induces the formation of local flux closure spin configurations that sometimes compete with the magnetostatic interaction.

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L. Salmon, V. Schánilec, J. Coraux, B. Canals, N. Rougemaille. 2023-10-18. Effective interaction quenching in artificial kagom\'e spin chains. https://arxiv.org/abs/2310.11933

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