Nature of the antiferromagnetic to valence-bond-solid quantum phase transition in a 2D XY-model with four-site interactions
Strongly Correlated Electrons
2007-05-23 v1
Abstract
We report large-scale quantum Monte Carlo calculations at the T=0 antiferromagnetic to valence-bond-solid (VBS) transition of a two-dimensional S=1/2 XY model with four-spin interactions. Finite-size scaling suggests a discontinuous spin stiffness, but a continuous VBS order-parameter. We propose that this is a continuous VBS transition without critical spin fluctuations. We also argue that the system is close to a point, in an extended parameter space, where both the magnetic and VBS fluctuations are critical--possibly a deconfined quantum-critical point.
Keywords
Cite
@article{arxiv.cond-mat/0604451,
title = {Nature of the antiferromagnetic to valence-bond-solid quantum phase transition in a 2D XY-model with four-site interactions},
author = {A. W. Sandvik and R. Melko},
journal= {arXiv preprint arXiv:cond-mat/0604451},
year = {2007}
}
Comments
4+ pages, 4 figures