Physical Review A

Phase diffusion and the output properties of a cw atom-laser

M. Naraschewski, Axel Schenzle, Hartmut Wallis

Published Jul 1, 1997• 38 citations

Abstract

We study an output coupler for matter waves that could be used to develop a cw atom-laser, based on current Bose-Einstein-condensation experiments with alkali-metal atoms. Assuming a cw pump mechanism for the condensate and taking into account losses due to outgoing atoms allows a description of the output by a coherently driven and damped Schr\"odinger equation. By contrast to a pulsed atom-laser output the stationary outgoing matter wave is extremely monoenergetic. Phase fluctuations of the condensate and technical noise limit the coherence length of the output beam. Using a Monte Carlo simulation we obtain the spatial correlation function of the output wave function, also including the influence of gravity.

DOI: 10.1103/physreva.56.603

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