title: Dark-state cooling of atoms by superfluid immersion.
abstract: We propose and analyze a scheme to cool atoms in an optical lattice to ultralow temperatures within a Bloch band and away from commensurate filling. The protocol is inspired by ideas from dark-state laser cooling but replaces electronic states with motional levels and spontaneous emission of photons by emission of phonons into a Bose-Einstein condensate, in which the lattice is immersed. In our model, achievable temperatures correspond to a small fraction of the Bloch bandwidth and are much lower than the reservoir temperature. This is also a novel realization of an open quantum optical system, where known tools are combined with new ideas involving cooling via a reservoir.
authors.affiliation: Institute for Quantum Optics and Quantum Information of the Austrian Academy of Sciences, A-6020 Innsbruck, Austria.
authors.forename: A
authors.initials: A
authors.lastname: Griessner
authors.forename: A J
authors.initials: AJ
authors.lastname: Daley
authors.forename: S R
authors.initials: SR
authors.lastname: Clark
authors.forename: D
authors.initials: D
authors.lastname: Jaksch
authors.forename: P
authors.initials: P
authors.lastname: Zoller