Cumulant expansion for systems with large spins
Statistical Mechanics
2009-10-31 v3
Abstract
A method is proposed for obtaining a systematic expansion of thermodynamic functions of spin systems with large spin S in powers of 1/S. It uses the cumulant technique and a coherent-state representation of the partition function Z. The expansion of Z in terms of cumulants yields an effective classical Hamiltonian with temperature-dependent quantum corrections. For the Heisenberg quantum Hamiltonian, they have a non-Heisenberg form. The effective Hamiltonian can be solved by methods familiar for classical systems.
Keywords
Cite
@article{arxiv.cond-mat/9811254,
title = {Cumulant expansion for systems with large spins},
author = {K. Kladko and P. Fulde and D. A. Garanin},
journal= {arXiv preprint arXiv:cond-mat/9811254},
year = {2009}
}
Comments
6 pages, 6 figures. Final published version