{ "id": "2208.04014", "version": "v1", "published": "2022-08-08T09:52:37.000Z", "updated": "2022-08-08T09:52:37.000Z", "title": "Thermodynamics and criticality of su($m$) spin chains of Haldane-Shastry type", "authors": [ "Federico Finkel", "Artemio González-López" ], "comment": "12 pages, 2 figures", "categories": [ "cond-mat.stat-mech", "math-ph", "math.MP", "quant-ph" ], "abstract": "We study the thermodynamics and critical behavior of su($m$) spin chains of Haldane-Shastry type at zero chemical potential, both in the $A_{N-1}$ and $BC_N$ cases. We evaluate in closed form the free energy per spin for arbitrary values of $m$, from which we derive explicit formulas for the energy, entropy and specific heat per spin. In particular, we find that the specific heat features a single Schottky peak, whose temperature is well approximated for $m\\lesssim10$ by the corresponding temperature for an $m$-level system with uniformly spaced levels. We show that at low temperatures the free energy per spin of the models under study behaves as that of a one-dimensional conformal field theory with central charge $c=m-1$ (with the only exception of the Frahm-Inozemtsev chain with zero value of its parameter). However, from a detailed study of the ground state degeneracy and the low-energy excitations, we conclude that these models are only critical in the antiferromagnetic case, with a few exceptions that we fully specify.", "revisions": [ { "version": "v1", "updated": "2022-08-08T09:52:37.000Z" } ], "analyses": { "keywords": [ "spin chains", "haldane-shastry type", "thermodynamics", "free energy", "criticality" ], "note": { "typesetting": "TeX", "pages": 12, "language": "en", "license": "arXiv", "status": "editable" } } }