The fate of spinons in spontaneously dimerised spin-1/2 ladders
Strongly Correlated Electrons
2009-10-31 v2
Abstract
We study a weakly coupled, frustrated two-leg spin-1/2 Heisenberg ladder. For vanishing coupling between the chains, elementary excitations are deconfined, gapless spin-1/2 objects called spinons. We investigate the fate of spinons for the case of a weak interchain interaction. We show that despite a drastic change in ground state, which becomes spontaneously dimerised, spinons survive as elementary excitations but acquire a spectral gap. We furthermore determine the exact dynamical structure factor for several values of momentum transfer.
Keywords
Cite
@article{arxiv.cond-mat/9907303,
title = {The fate of spinons in spontaneously dimerised spin-1/2 ladders},
author = {Dave Allen and Fabian H. L. Essler and Alexander A. Nersesyan},
journal= {arXiv preprint arXiv:cond-mat/9907303},
year = {2009}
}
Comments
8 pages of revtex, 7 figures; discussion of physical picture for ground state and excitations in the "twistless" ladder expanded, version to appear in Phys Rev B