Physics – Condensed Matter – Statistical Mechanics
Scientific paper
2002-12-05
Physics
Condensed Matter
Statistical Mechanics
20 pages, 30 figures, to appear in J. Stat. Phys
Scientific paper
We formulate a new method of performing high-temperature series expansions for the spin-half Heisenberg model or, more generally, for SU($n$) Heisenberg model with arbitrary $n$. The new method is a novel extension of the well-established finite cluster method. Our method emphasizes hidden combinatorial aspects of the high-temperature series expansion, and solves the long-standing problem of how to efficiently calculate correlation functions of operators acting at widely separated sites. Series coefficients are expressed in terms of cumulants, which are shown to have the property that all deviations from the lowest-order nonzero cumulant can be expressed in terms of a particular kind of moment expansion. These ``quasi-moments'' can be written in terms of corresponding ``quasi-cumulants'', which enable us to calculate higher-order terms in the high-temperature series expansion. We also present a new technique for obtaining the low-order contributions to specific heat from finite clusters.
No associations
LandOfFree
A New Method of the High Temperature Series Expansion does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with A New Method of the High Temperature Series Expansion, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and A New Method of the High Temperature Series Expansion will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-702813