Phase diagram of a Heisenberg spin-Peierls model with quantum phonons
Abstract
Using a new version of the density-matrix renormalization group we determine the phase diagram of a model of an antiferromagnetic Heisenberg spin chain where the spins interact with quantum phonons. A quantum phase transition from a gapless spin-fluid state to a gapped dimerized phase occurs at a non-zero value of the spin-phonon coupling. The transition is in the same universality class as that of a frustrated spin chain, which the model maps to in the anti-adiabatic limit. We argue that realistic modeling of known spin-Peierls materials should include the effects of quantum phonons.
Keywords
Cite
@article{arxiv.cond-mat/9812409,
title = {Phase diagram of a Heisenberg spin-Peierls model with quantum phonons},
author = {Robert J. Bursill and Ross H. McKenzie and Chris J. Hamer},
journal= {arXiv preprint arXiv:cond-mat/9812409},
year = {2009}
}
Comments
RevTeX, 5 pages, 3 eps figures included using epsf. Improved theories in adiabatic and non-adiabatic regimes give better agreement with DMRG. This version accepted in Physical Review Letters