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Dynamic spin-glass behavior in a disorder-free, two-component model of quantum frustrated magnets

Frederic Mila·David Dean
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Abstract

Motivated by the observation of a spin-glass transition in almost disorder-free Kagome antiferromagnets, and by the specific form of the effective low-energy model of the S=1/2, trimerized Kagome antiferromagnet, we investigate the possibility to obtain a spin-glass behavior in two-component, disorder-free models. We concentrate on a toy-model, a modified Ashkin-Teller model in a magnetic field that couples only to one species of spins, for which we prove that a dynamic spin-glass behavior occurs. The dynamics of the magnetization is closely related to that of the underlying Ising model in zero field in which spins and pseudo-spins are intimately coupled. The spin-glass like history dependence of the magnetization is a consequence of the ageing of the underlying Ising model.

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Frederic Mila, David Dean. 2002-01-23. Dynamic spin-glass behavior in a disorder-free, two-component model of quantum frustrated magnets. https://doi.org/10.1140/epjb%2Fe20020093

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