Effective interaction quenching in artificial kagomé spin chains
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 one-dimensional artificial kagomé spin chains. Imaging arrested microstates resulting from a field demagnetization protocol and analyzing their pairwise spin correlations in real space, we unveil a nonequilibrated 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 interpret this quenching mechanism as a kinetic hinderance occurring upon demagnetization, which induces the formation of local flux closure spin configurations that compete with those energetically favored by the magnetostatic interaction coupling the nanomagnets.
L. Salmon, V. Schánilec, J. Coraux, B. Canals, and N. Rougemaille