Magnetocaloric effect in integrable spin-s chains

TL;DR

This paper provides an exact analysis of the magnetocaloric effect in integrable high-spin chains, revealing quantum critical points and thermodynamic behaviors using Bethe ansatz and transfer matrix methods.

Contribution

It introduces an exact computation of the Grüneisen parameter and thermodynamic properties for high-spin chains, identifying quantum critical points.

Findings

Exact Grüneisen parameter calculation for spin-s chains

Identification of quantum critical points at specific magnetic fields

Analysis of entropy and isentropes in the (H,T) plane

Abstract

We study the magnetocaloric effect for the integrable antiferromagnetic high-spin chain. We present an exact computation of the Gr\"uneisen parameter, which is closely related to the magnetocaloric effect, for the quantum spin-s chain on the thermodynamical limit by means of Bethe ansatz techniques and the quantum transfer matrix approach. We have also calculated the entropy S and the isentropes in the (H,T) plane. We have been able to identify the quantum critical points H_c^{(s)}=2/(s+1/2) looking at the isentropes and/or the characteristic behaviour of the Gr\"uneisen parameter.