Determination of the Number of Atoms Trapped in an Optical Cavity
J. McKeever, J. R. Buck, A. David. Boozer, Harry J. Kimble · Physical Review Letters · 2004
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.