paper

Quantum criticality of a Bose gas in an optical lattice near the Mott transition

arXiv:1107.1314 · doi:10.1103/PhysRevA.85.011602

Abstract

We derive the equation of state of bosons in an optical lattice in the framework of the Bose-Hubbard model. Near the density-driven Mott transition, the expression of the pressure P(μ,T) versus chemical potential and temperature is similar to that of a dilute Bose gas but with renormalized mass m^* and scattering length a^*. m^* is the mass of the elementary excitations at the quantum critical point governing the transition from the superfluid phase to the Mott insulating phase, while a^* is related to their effective interaction at low energy. We use a nonperturbative renormalization-group approach to compute these parameters as a function of the ratio t/U between hopping amplitude and on-site repulsion.

v1) 4 pages, 6 figures. v2) Significant rewriting (new title) with more emphasis on the quantum critical behavior near the Mott transition

References in corpus (15)

Cited by in corpus (11)