Correlation functions of the XXZ model for Δ < − 1

Abstract

A new approach to the correlation functions is presented for the XXZ model in the antiferroelectric regime. The method is based on the recent realization of the quantum affine symmetry using vertex operators. With the aid of a boson representation for the latter, an integral formula is found for correlation functions of arbitrary local operators. As a special case it reproduces the spontaneous staggered polarization obtained earlier by Baxter.