Radio-frequency output coupling of the Bose-Einstein condensate for atom lasers

We develop the quantum-mechanical description of output coupling of macrosc opic coherent matter waves from a Bose-Einstein condensate (BEC) via a radi o-frequency field in the pulsed and cw limits for both strong and weak fiel d coupling. The theory is converted into a Fock state description to point out the stimulated (in Bose particle) nature of the output coupling. A usef ul analogy with the theory of molecular photodissociation is used to explai n the various regimes of output coupling BECs using radiation sources. We p resent specific calculations of the rates of output coupling as a function of the number of Bose atoms in the condensate and the frequency, detuning, and intensity of the radio-frequency field. [S1050-2947(99)00805-7].