Low temperature thermodynamics of inverse square spin models in one dimension

W. Hofstetter; W. Zwerger

doi:10.1007/s100510050499

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Low temperature thermodynamics of inverse square spin models in one dimension

W. Hofstetter·W. Zwerger

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Abstract

We present a field-theoretic renormalization group calculation in two loop order for classical O(N)-models with an inverse square interaction in the vicinity of their lower critical dimensionality one. The magnetic susceptibility at low temperatures is shown to diverge like $T^{-a} \exp(b/T)$ with $a=(N-2)/(N-1)$ and $b=2π^2/(N-1)$. From a comparison with the exactly solvable Haldane-Shastry model we find that the same temperature dependence applies also to ferromagnetic quantum spin chains.

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W. Hofstetter, W. Zwerger. 1998-04-29. Low temperature thermodynamics of inverse square spin models in one dimension. https://doi.org/10.1007/s100510050499

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