Non-perturbative renormalization-group approach to the Bose-Hubbard model
Quantum Gases
2011-06-03 v3
Abstract
We present a non-perturbative renormalization-group approach to the Bose-Hubbard model. By taking as initial condition of the RG flow the (local) limit of decoupled sites, we take into account both local and long-distance fluctuations in a nontrivial way. This approach yields a phase diagram in very good quantitative agreement with the quantum Monte Carlo results and reproduces the two universality classes of the superfluid--Mott-insulator transition with a good estimate of the critical exponents. Furthermore, it reveals the crucial role of the "Ginzburg length" as a crossover length between a weakly- and a strongly-correlated superfluid phase.
Cite
@article{arxiv.1012.0166,
title = {Non-perturbative renormalization-group approach to the Bose-Hubbard model},
author = {A. Rancon and N. Dupuis},
journal= {arXiv preprint arXiv:1012.0166},
year = {2011}
}
Comments
v2) revised version (new title and abstract, significant rewritting), 4 pages, 4 figures