title: Cavity-based single atom preparation and high-fidelity hyperfine state readout.
abstract: We prepare and detect the hyperfine state of a single 87Rb atom coupled to a fiber-based high-finesse cavity on an atom chip. The atom is extracted from a Bose-Einstein condensate and trapped at the maximum of the cavity field, resulting in a reproducibly strong atom-cavity coupling. We use the cavity reflection and transmission signal to infer the atomic hyperfine state with a fidelity exceeding 99.92% in a readout time of 100  μs. The atom is still trapped after detection.
authors.affiliation: Laboratoire Kastler-Brossel, ENS, CNRS, UPMC, 24 rue Lhomond, 75005 Paris, France.
authors.forename: Roger
authors.initials: R
authors.lastname: Gehr
authors.forename: Jürgen
authors.initials: J
authors.lastname: Volz
authors.forename: Guilhem
authors.initials: G
authors.lastname: Dubois
authors.forename: Tilo
authors.initials: T
authors.lastname: Steinmetz
authors.forename: Yves
authors.initials: Y
authors.lastname: Colombe
authors.forename: Benjamin L
authors.initials: BL
authors.lastname: Lev
authors.forename: Romain
authors.initials: R
authors.lastname: Long
authors.forename: Jérôme
authors.initials: J
authors.lastname: Estève
authors.forename: Jakob
authors.initials: J
authors.lastname: Reichel