English

Sweeping from the superfluid to Mott phase in the Bose-Hubbard model

Statistical Mechanics 2007-05-23 v2 Quantum Physics

Abstract

We study the sweep through the quantum phase transition from the superfluid to the Mott state for the Bose-Hubbard model with a time-dependent tunneling rate J(t)J(t). In the experimentally relevant case of exponential decay, J(t)eγtJ(t)\propto e^{-\gamma t}, an adapted mean-field expansion for large fillings nn yields a scaling solution for the fluctuations. This enables us to analytically calculate the evolution of the number and phase variations (on-site) and correlations (off-site) for slow (γμ\gamma\ll\mu), intermediate, and fast (non-adiabatic γμ\gamma\gg\mu) sweeps, where μ\mu is the chemical potential. Finally, we derive the dynamical decay of the off-diagonal long-range order as well as the temporal shrinkage of the superfluid fraction in a persistent ring-current setup.

Keywords

Cite

@article{arxiv.cond-mat/0605121,
  title  = {Sweeping from the superfluid to Mott phase in the Bose-Hubbard model},
  author = {Ralf Schützhold and Michael Uhlmann and Yan Xu and Uwe R. Fischer},
  journal= {arXiv preprint arXiv:cond-mat/0605121},
  year   = {2007}
}

Comments

4 pages of RevTex4, 1 figure; to appear in Physical Review Letters