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arXiv · 1011.5296

Quantum kinetic theory model of a continuous atom laser

G. R. Dennis·Matthew J. Davis·J. J. Hope
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Abstract

We investigate the feasible limits for realising a continuously evaporated atom laser with high-temperature sources. A plausible scheme for realising a truly continuous atom laser is to outcouple atoms from a partially condensed Bose gas, whilst continuously reloading the system with non-condensed thermal atoms and performing evaporative cooling. Here we use quantum kinetic theory to model this system and estimate feasible limits for the operation of such a scheme. For sufficiently high temperatures, the figure of merit for the source is shown to be the phase-space flux. The dominant process limiting the usage of sources with low phase-space flux is the three-body loss of the condensed gas. We conclude that certain double-magneto-optical trap (MOT) sources may produce substantial mean condensate numbers through continuous evaporation, and provide an atom laser source with a narrow linewidth and reasonable flux.

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G. R. Dennis, Matthew J. Davis, J. J. Hope. 2010-11-24. Quantum kinetic theory model of a continuous atom laser. https://doi.org/10.1103/physreva.86.013640

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