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Neel Temperature of Quasi-Low-Dimensional Heisenberg Antiferromagnets

C. Yasuda·S. Todo·K. Hukushima·F. Alet·M. Keller·M. Troyer·H. Takayama
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Abstract

The Néel temperature, $T_{\rm N}$, of quasi-one- and quasi-two-dimensional antiferromagnetic Heisenberg models on a cubic lattice is calculated by Monte Carlo simulations as a function of inter-chain (inter-layer) to intra-chain (intra-layer) coupling $J'/J$ down to $J'/J\simeq 10^{-3}$. We find that $T_{\rm N}$ obeys a modified random-phase approximation-like relation for small $J'/J$ with an effective universal renormalized coordination number, independent of the size of the spin. Empirical formulae describing $T_{\rm N}$ for a wide range of $J'$ and useful for the analysis of experimental measurements are presented.

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C. Yasuda, S. Todo, K. Hukushima, F. Alet, M. Keller, M. Troyer, H. Takayama. 2005-04-28. Neel Temperature of Quasi-Low-Dimensional Heisenberg Antiferromagnets. https://doi.org/10.1103/physrevlett.94.217201

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