arXiv:cond-mat/9903112 · Journal of the Physical Society of Japan

Excited State TBA and Functional Relations in Spinless Fermion Model

Kazumitsu Sakai

Published Jun 15, 1999• 6 citations

Abstract

The excited state thermodynamic Bethe ansatz (TBA) equations for the spinless Fermion model are presented by the quantum transfer matrix (QTM) approach. We introduce a more general family called T-functions and explore functional relations among them (T-system) and their certain combinations (Y-system). {}From their analytical property, we derive a closed set of non-linear integral equations which characterize the correlation length of $$ at any finite temperatures. Solving these equations numerically, we explicitly determine the correlation length, which coincides with earlier results with high accuracy.

DOI: 10.1143/jpsj.68.1789

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