Non-Markovian dynamics in continuous-wave atom lasers

The non-Markovian dynamics of a continuous-wave atom laser model including gravitational effects and interactions inside the Bose-Einstein condensate is studied. A generalization of the time-convolutionless projection operator technique presented in this article enables a correct modeling of memory effects in the atom laser which takes into account correlations in the initial state of the combined atom-reservoir system. This generalization allows the computation of both the occupation number of the condensate and the spectrum of the atoms coupled out of the condensate. The non-Markovian evolution is shown to yield substantial deviations from results obtained in the Born-Markov approximation.