Ring Exchange and Phase Separation in the Two-dimensional Boson Hubbard model
Statistical Mechanics
2009-11-11 v1
Abstract
We present Quantum Monte Carlo simulations of the soft-core bosonic Hubbard model with a ring exchange term K. For values of K which exceed roughly half the on-site repulsion U, the density is a non-monotonic function of the chemical potential, indicating that the system has a tendency to phase separate. This behavior is confirmed by an examination of the density-density structure factor and real space images of the boson configurations. Adding a near-neighbor repulsion can compete with phase separation, but still does not give rise to a stable normal Bose liquid.
Cite
@article{arxiv.cond-mat/0505347,
title = {Ring Exchange and Phase Separation in the Two-dimensional Boson Hubbard model},
author = {V. G. Rousseau and R. T. Scalettar and G. G. Batrouni},
journal= {arXiv preprint arXiv:cond-mat/0505347},
year = {2009}
}
Comments
12 pages, 23 figures