arXiv:1001.5450 · Journal of Statistical Mechanics Theory and Experiment

Thermodynamics of the quantumsu(1, 1) Landau–Lifshitz model

A Melikyan, A Pinzul

Published Jun 3, 2010• 7 citations

Abstract

We present the thermodynamics of the quantum su (1, 1) Landau–Lifshitz model, following our earlier exposition of the quantum integrability of the theory, which is based on the construction of self-adjoint extensions, leading to a regularized quantum Hamiltonian for an arbitrary n -particle sector. Starting from general discontinuity properties of the functions used to construct the self-adjoint extensions, we derive the thermodynamic Bethe ansatz equations. We show that due to the non-symmetric and singular kernel, the self-consistency implies that only negative chemical potential values are allowed, which leads to the conclusion that, unlike its su (2) counterpart, the su (1, 1) LL theory at T = 0 has no instabilities.

DOI: 10.1088/1742-5468/2010/06/p06007

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