TY - JOUR T1 - Phase diagram of the Bose Kondo-Hubbard model JF - Physical Review A Y1 - 2011 A1 - Michael Foss-Feig A1 - Ana Maria Rey AB - We study a bosonic version of the Kondo lattice model with an on-site repulsion in the conduction band, implemented with alkali atoms in two bands of an optical lattice. Using both weak and strong-coupling perturbation theory, we find that at unit filling of the conduction bosons the superfluid to Mott insulator transition should be accompanied by a magnetic transition from a ferromagnet (in the superfluid) to a paramagnet (in the Mott insulator). Furthermore, an analytic treatment of Gutzwiller mean-field theory reveals that quantum spin fluctuations induced by the Kondo exchange cause the otherwise continuous superfluid to Mott-insulator phase transition to be first order. We show that lattice separability imposes a serious constraint on proposals to exploit excited bands for quantum simulations, and discuss a way to overcome this constraint in the context of our model by using an experimentally realized non-separable lattice. A method to probe the first-order nature of the transition based on collapses and revivals of the matter-wave field is also discussed. VL - 84 UR - http://arxiv.org/abs/1103.0245v2 CP - 5 J1 - Phys. Rev. A U5 - 10.1103/PhysRevA.84.053619 ER -