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The open Haldane–Shastry chain: thermodynamics and criticality Finkel Morgenstern, Federico González López, Artemio 51-73 Integrable spin chains and vertex models Solvable lattice models Quantum criticality Física matemática 2212 Física Teórica Está depositada la versión enviada a la revista del artículo We study the thermodynamics and criticality of the su(m|n) Haldane-Shastry chain of BC ( N ) type with a general chemical potential term. We first derive a complete description of the spectrum of this model in terms of BC ( N )-type motifs, from which we deduce a representation for the partition function as the trace of a product of site-dependent transfer matrices. In the thermodynamic limit, this formula yields a simple expression for the free energy per spin in terms of the Perron-Frobenius eigenvalue of the continuum limit of the transfer matrix. Evaluating this eigenvalue we obtain closed-form expressions for the thermodynamic functions of the chains with m, n <= 2. Using the motif-based description of the spectrum derived here, we study in detail the ground state of these models and their low energy excitations. In this way we identify the critical intervals in chemical potential space and compute their corresponding Fermi velocities. By contrast with previously studied models of this type, we find in some cases two types of low energy excitations with linear energy-quasimomentum relation. Finally, we determine the central charge of all the critical phases by analyzing the low-temperature behavior of the expression for the free energy per spin. Ministerio de Ciencia e Innovación (España) Universidad Complutense de Madrid Depto. de Física Teórica Fac. de Ciencias Físicas TRUE pub 2024-01-25T10:08:40Z 2024-01-25T10:08:40Z 2022-09-14 journal article VoR https://hdl.handle.net/20.500.14352/95314 1742-5468 10.1088/1742-5468/ac8801 eng info:eu-repo/grantAgreement/PGC2018-094898-B-I00 info:eu-repo/grantAgreement/G/6400100/3000 Finkel F and González-López A 2022 The open Haldane–Shastry chain: thermodynamics and criticality 2022 093102 open access application/pdf IOP Publishing Ltd and SISSA Medialab srl