Flow equation solution for the weak to strong-coupling crossover in the sine-Gordon model
Statistical Mechanics
2009-10-31 v2 Strongly Correlated Electrons
High Energy Physics - Theory
Abstract
A continuous sequence of infinitesimal unitary transformations, combined with an operator product expansion for vertex operators, is used to diagonalize the quantum sine-Gordon model for 2 pi < beta^2 < infinity. The leading order of this approximation already gives very accurate results for the single-particle gap in the strong-coupling phase. This approach can be understood as an extension of perturbative scaling theory since it links weak to strong-coupling behavior in a systematic expansion. The approach should also be useful for other strong-coupling problems that can be formulated in terms of vertex operators.
Cite
@article{arxiv.cond-mat/9908048,
title = {Flow equation solution for the weak to strong-coupling crossover in the sine-Gordon model},
author = {Stefan Kehrein},
journal= {arXiv preprint arXiv:cond-mat/9908048},
year = {2009}
}
Comments
4 pages, 1 figure, minor changes (typo in Eq. (3) corrected, references added), published version