TY - JOUR T1 - Bogoliubov approach to superfluidity of atoms in an optical lattice JF - Journal of Physics B: Atomic, Molecular and Optical Physics Y1 - 2003 A1 - Ana Maria Rey A1 - Keith Burnett A1 - Robert Roth A1 - Mark Edwards A1 - Carl J. Williams A1 - Charles W. Clark AB - We use the Bogoliubov theory of atoms in an optical lattice to study the approach to the Mott-insulator transition. We derive an explicit expression for the superfluid density based on the rigidity of the system under phase variations. This enables us to explore the connection between the quantum depletion of the condensate and the quasi-momentum distribution on the one hand and the superfluid fraction on the other. The approach to the insulator phase may be characterized through the filling of the band by quantum depletion, which should be directly observable via the matter wave interference patterns. We complement these findings by self-consistent Hartree-Fock-Bogoliubov-Popov calculations for one-dimensional lattices including the effects of a parabolic trapping potential. VL - 36 U4 - 825 - 841 UR - http://arxiv.org/abs/cond-mat/0210550v2 CP - 5 J1 - J. Phys. B: At. Mol. Opt. Phys. U5 - 10.1088/0953-4075/36/5/304 ER -