{"paper":{"title":"Thermodynamics of O(N) Antiferromagnets in 2+1 Dimensions","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["hep-lat","hep-ph"],"primary_cat":"cond-mat.str-el","authors_text":"Christoph P. Hofmann","submitted_at":"2009-09-28T23:47:59Z","abstract_excerpt":"Within the framework of effective Lagrangians we calculate the free energy density for an O($N$) antiferromagnet in 2+1 dimensions up to three-loop order in the perturbative expansion and derive the low-temperature series for various thermodynamic quantities. In particular, we show that the magnon-magnon interaction in the O(3) antiferromagnet in $d$=2+1 -- the O(3)-invariant quantum Heisenberg antiferromagnet on a square or a honeycomb lattice -- is very weak and repulsive and manifests itself through a term proportional to five powers of the temperature in the free energy density. Remarkably"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"0909.5239","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}