title: Spin squeezing and light entanglement in coherent population trapping.
abstract: We show that strong squeezing and entanglement can be generated at the output of a cavity containing atoms interacting with two fields in a coherent population trapping situation, on account of a nonlinear Faraday effect experienced by the fields close to a dark-state resonance in a cavity. Moreover, the cavity provides a feedback mechanism allowing to reduce the quantum fluctuations of the ground state spin, resulting in strong steady state spin squeezing.
authors.affiliation: Laboratoire Charles Fabry de l'Institut d'Optique, F91403 Orsay cedex, France.
authors.forename: A
authors.initials: A
authors.lastname: Dantan
authors.forename: J
authors.initials: J
authors.lastname: Cviklinski
authors.forename: E
authors.initials: E
authors.lastname: Giacobino
authors.forename: M
authors.initials: M
authors.lastname: Pinard