Multi-Chain Mean-Field Theory of Quasi One-Dimensional Quantum Spin Systems
Abstract
A multi-chain mean-field theory is developed and applied to a two-dimensional system of weakly coupled S=1/2 Heisenberg chains. The environment of a chain C_0 is modeled by a number of neighbor chains C_d, d = +/-1,...,+/-n, with the edge chains (d=+/-n) coupled to a staggered field. Using a quantum Monte Carlo method, the effective (2n+1)-chain Hamiltonian is solved self-consistently for up to 4. The results are compared with simulation results for the original Hamiltonian on large rectangular lattices. Both methods show that the staggered magnetization M for small interchain couplings alpha behaves as M=A*alpha^1/2 enhanced by a multiplicative logarithmic correction.
Keywords
Cite
@article{arxiv.cond-mat/9904218,
title = {Multi-Chain Mean-Field Theory of Quasi One-Dimensional Quantum Spin Systems},
author = {Anders W. Sandvik},
journal= {arXiv preprint arXiv:cond-mat/9904218},
year = {2009}
}
Comments
4 pages, 3 figures. Results for larger numbers of chains included (up to 9). More extensive discussion of finite-size corrections for rectangular lattices