Transition from Haldane Phase to Spin Liquid and Incommensurate Correlation in Spin-1/2 Heisenberg Chains
Abstract
The bulk properties and impurity effect in the one-dimensional S=1/2 Heisenberg model with dimerization and next-nearest-neighbor exchange are studied by the density matrix renormalization group (DMRG) and exact diagonalization methods. This model widely covers the S=1 Heisenberg model, two-leg ladders, bond-alternating chains and the S=1/2 Heisenberg model. Almost the whole parameter space belongs to the Haldane phase. In the non-dimerizing limit a transition to a kind of spin liquid takes place, characterized by the delocalized spin polarization. This transition causes the distinct impurity effects between a spin-Peierls compound CuGeO_{3} and the Haldane systems. Experimental aspects of a bond-alternating compound CuNb_{2}O_{6} are also discussed. Furthermore, the incommensurate correlation arising in this model is extensively studied, and a phase diagram is constructed.
Keywords
Cite
@article{arxiv.cond-mat/9902311,
title = {Transition from Haldane Phase to Spin Liquid and Incommensurate Correlation in Spin-1/2 Heisenberg Chains},
author = {Shinji Watanabe and Hisatoshi Yokoyama},
journal= {arXiv preprint arXiv:cond-mat/9902311},
year = {2009}
}
Comments
Submitted to J. Phys. Soc. Jpn. 25 pages. 32 figures. Figs.13-32 (1.72MB) are available on request by E-mail or hard copy