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Asymptotic scaling of the square lattice quantum Heisenberg antiferromagnet

Jae-Kwon Kim·Matthias Troyer
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Abstract

We present thermodynamic measurements of various physical observables of the two dimensional S=1/2 isotropic quantum Heisenberg antiferromagnet on a square lattice, obtained by quantum Monte Carlo. In particular we have been able to measure the infinite volume limit of the uniform susceptibility up to the inverse temperature beta=40, the analysis of which reveals the correct asymptotic behavior in excellent agreement with the prediction of chiral perturbation theory. The controversy over the existence of a crossover from quantum critical to renormalized classical regime is resolved.

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Jae-Kwon Kim, Matthias Troyer. 1997-10-03. Asymptotic scaling of the square lattice quantum Heisenberg antiferromagnet. https://doi.org/10.1103/physrevlett.80.2705

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