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Stationary quantum statistics of a non-Markovian atom laser

A. S. Bradley·J. J. Hope·M. J. Collett
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Abstract

We present a steady state analysis of a quantum-mechanical model of an atom laser. A single-mode atomic trap coupled to a continuum of external modes is driven by a saturable pumping mechanism. In the dilute flux regime, where atom-atom interactions are negligible in the output, we have been able to solve this model without making the Born-Markov approximation. The more exact treatment has a different effective damping rate and occupation of the lasing mode, as well as a shifted frequency and linewidth of the output. We examine gravitational damping numerically, finding linewidths and frequency shifts for a range of pumping rates. We treat mean field damping analytically, finding a memory function for the Thomas-Fermi regime. The occupation and linewidth are found to have a nonlinear scaling behavior which has implications for the stability of atom lasers.

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A. S. Bradley, J. J. Hope, M. J. Collett. 2002-10-31. Stationary quantum statistics of a non-Markovian atom laser. https://doi.org/10.1103/physreva.68.063611

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