title: Dicke-model phase transition in the quantum motion of a Bose-Einstein condensate in an optical cavity.
abstract: We show that the motion of a laser-driven Bose-Einstein condensate in a high-finesse optical cavity realizes the spin-boson Dicke model. The quantum phase transition of the Dicke model from the normal to the superradiant phase corresponds to the self-organization of atoms from the homogeneous into a periodically patterned distribution above a critical driving strength. The fragility of the ground state due to photon measurement induced backaction is calculated.
authors.affiliation: Research Institute for Solid State Physics and Optics, H-1525 Budapest P.O. Box 49, Hungary.
authors.forename: D
authors.initials: D
authors.lastname: Nagy
authors.forename: G
authors.initials: G
authors.lastname: Kónya
authors.forename: G
authors.initials: G
authors.lastname: Szirmai
authors.forename: P
authors.initials: P
authors.lastname: Domokos