arXiv:cond-mat/9705196 · Physical review. B, Condensed matter
Quasi-one-dimensional spin- 12 Heisenberg magnets in their ordered phase: Correlation functions
Fabian H. L. Eßler, Alexei M. Tsvelik, Gesualdo Delfino A
Abstract
We study weakly coupled antiferromagnetic spin chains in their ordered phase by combining an exact solution of the single-chain problem with a random-phase-approximation 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 form-factor approach to quantum correlation functions. We consider both antiferromagnetic order encountered in quasi-one-dimensional materials such as ${\mathrm{KCuF}}_{3}$ and spin-Peierls order as found in ${\mathrm{CuGeO}}_{3}.$