title: Determination of the number of atoms trapped in an optical cavity.
abstract: The number of atoms trapped within the mode of an optical cavity is determined in real time by monitoring the transmission of a weak probe beam. Continuous observation of atom number is accomplished in the strong coupling regime of cavity quantum electrodynamics and functions in concert with a cooling scheme for radial atomic motion. The probe transmission exhibits sudden steps from one plateau to the next in response to the time evolution of the intracavity atom number, from N>or=3 to N=2-->1-->0 atoms, with some trapping events lasting over 1 s.
authors.affiliation: Norman Bridge Laboratory of Physics 12-33, California Institute of Technology, Pasadena, California 91125, USA.
authors.forename: J
authors.initials: J
authors.lastname: McKeever
authors.forename: J R
authors.initials: JR
authors.lastname: Buck
authors.forename: A D
authors.initials: AD
authors.lastname: Boozer
authors.forename: H J
authors.initials: HJ
authors.lastname: Kimble