We study weakly coupled antiferromagnetic spin chains in their ordered phase by combinining an exact solution of the single-chain problem with an RPA analysis of the interchain interaction. A single chain is described by a quantum Sine-Gordon model and dynamical staggered susceptibilities are determined by employing the formfactor approach to quantum correlation functions. We consider both antiferromagnetic order encountered in quasi-1D materials like KCuF3 and spin-Peierls order as found in CuGeO3.
@article{arxiv.cond-mat/9705196,
title = {Quasi-1D spin-1/2 Heisenberg magnets in their ordered phase: correlation functions},
author = {Fabian H. L. Essler and Alexei M. Tsvelik and Gesulado Delfino},
journal= {arXiv preprint arXiv:cond-mat/9705196},
year = {2009}
}