title: Superradiant rayleigh scattering and collective atomic recoil lasing in a ring cavity.
abstract: Collective interaction of light with an atomic gas can give rise to superradiant instabilities. We experimentally study the sudden buildup of a reverse light field in a laser-driven high-finesse ring cavity filled with ultracold thermal or Bose-Einstein condensed atoms. While superradiant Rayleigh scattering from atomic clouds is normally observed only at very low temperatures (i.e., well below 1 microK), the presence of the ring cavity enhances cooperativity and allows for superradiance with thermal clouds as hot as several 10 microK. A characterization of the superradiance at various temperatures and cooperativity parameters allows us to link it to the collective atomic recoil laser.
authors.affiliation: Physikalisches Institut, Eberhard-Karls-Universität Tübingen, Auf der Morgenstelle 14, D-72076 Tübingen, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Slama
authors.forename: S
authors.initials: S
authors.lastname: Bux
authors.forename: G
authors.initials: G
authors.lastname: Krenz
authors.forename: C
authors.initials: C
authors.lastname: Zimmermann
authors.forename: Ph W
authors.initials: PW
authors.lastname: Courteille