arXiv:1603.00504 · Journal of Physics A Mathematical and Theoretical

Correlation functions of the integrable spin- s chain ∗

G A P Ribeiro, Andreas Klümper

Published May 12, 2016• 11 citations

Abstract

Abstract We study the correlation functions of su (2) invariant spin- s chains in the thermodynamic limit. We derive nonlinear integral equations for an auxiliary correlation function ω for any spin s and finite temperature T . For the spin-3/2 chain for arbitrary temperature and zero magnetic field we obtain algebraic expressions for the reduced density matrix of two-sites. In the zero temperature limit, the density matrix elements are evaluated analytically and appear to be given in terms of Riemann’s zeta function values of even and odd arguments.

DOI: 10.1088/1751-8113/49/25/254001

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