Theory of an atom laser

Abstract
Superconductivity, superfluidity, Bose-Einstein condensation, and laser amplification are all examples of a general mechanism involving the stimulated transfer of bosons into a specific quantum state. When the occupation number of the state is large, this mechanism may generate a macroscopic coherence for the state amplitude. In this paper, we demonstrate that the stimulated transfer of bosonic atoms into a given state of an optical or a magnetic trap can give rise to a coherent atomic source in analogy with the photon laser and we present a general model for such a device.