arXiv:cond-mat/0002219 · Journal of Physics A Mathematical and General
Asymptotic form of the two-point correlation function of theXXZspin chain
Yasuhiro Fujii, Miki Wadati
Abstract
Correlation functions of the XXZ spin chain in the critical regime are studied at zero temperature. They are exactly represented in the Fredholm determinant form and are related to an operator-valued Riemann-Hilbert problem. Analysing this problem we prove that a two-point correlation function is asymptotically expressed in terms of power functions of the distance between spin operators.