title: Nonequilibrium phase transition of interacting bosons in an intra-cavity optical lattice.
abstract: We investigate the nonlinear light-matter interaction of a Bose-Einstein condensate trapped in an external periodic potential inside an optical cavity which is weakly coupled to vacuum radiation modes and driven by a transverse pump field. Based on a generalized Bose-Hubbard model which incorporates a single cavity mode, we include the collective backaction of the atoms on the cavity light field and determine the nonequilibrium quantum phases within the nonperturbative bosonic dynamical mean-field theory. With the system parameters adapted to recent experiments, we find a quantum phase transition from a normal phase to a self-organized superfluid phase, which is related to the Hepp-Lieb-Dicke superradiance phase transition. For even stronger pumping, a self-organized Mott insulator phase arises.
authors: I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, 20355 Hamburg, Germany.
authors: M Reza
authors: MR
authors: Bakhtiari
authors: Institut für Laser-Physik, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany.
authors: A
authors: A
authors: Hemmerich
authors: Institute for Theoretical Physics, Universität Innsbruck, Technikerstraße 25, 6020 Innsbruck, Austria.
authors: H
authors: H
authors: Ritsch
authors: I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, 20355 Hamburg, Germany.
authors: M
authors: M
authors: Thorwart