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arXiv · 1906.07051

Nonordinary criticality at the edges of planar spin-1 Heisenberg antiferromagnets

Lukas Weber·Stefan Wessel
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Abstract

Dangling edge spins of dimerized two-dimensional spin-1 Heisenberg antiferromagnets are shown to exhibit nonordinary quantum critical correlations, akin to the scaling behavior observed in recently explored spin-1/2 systems. Based on large-scale quantum Monte Carlo simulations, we observe remarkable similarities between these two cases, and also examine the crossover to the fundamentally distinct behavior in the one-dimensional limit of strongly coupled edge spins. We complement our numerical analysis by a cluster mean-field theory that encompasses the qualitatively similar behavior for the spin-1 and the spin-1/2 case, and its dependence on the spatial edge spin configuration in a generic way.

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Lukas Weber, Stefan Wessel. 2019-09-04. Nonordinary criticality at the edges of planar spin-1 Heisenberg antiferromagnets. https://doi.org/10.1103/physrevb.100.054437

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