title: Observation of collective-emission-induced cooling of atoms in an optical cavity.
abstract: We report the observation of collective-emission-induced, velocity-dependent light forces. One-third of a falling sample containing 3 x 10(6) cesium atoms illuminated by a horizontal standing wave is stopped by cooperatively emitting light into a vertically oriented, confocal resonator. We observe decelerations up to 1500 m/s(2) and cooling to temperatures as low as 7 microK, well below the free-space Doppler limit. The measured forces substantially exceed those predicted for a single two-level atom.
authors.affiliation: Department of Physics, Stanford University, Stanford, California 94305-4060, USA.
authors.forename: Hilton W
authors.initials: HW
authors.lastname: Chan
authors.forename: Adam T
authors.initials: AT
authors.lastname: Black
authors.forename: Vladan
authors.initials: V
authors.lastname: Vuletić