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Control of an atom laser using feedback

S. A. Haine·A. J. Ferris·J. D. Close·J. J. Hope
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Abstract

A generalised method of using feedback to control Bose-Einstein condensates is introduced. The condensates are modelled by the Gross-Pitaevskii equation, so only semiclassical fluctations can be suppressed, and back-action from the measurement is ignored. We show that for any available control, a feedback scheme can be found to reduce the energy while the appropriate moment is still dynamic. We demonstrate these schemes by considering a condensate trapped in a harmonic potential that can be modulated in strength and position. The formalism of our feedback scheme also allows the inclusion of certain types of non-linear controls. If the non-linear interaction between the atoms can be controlled via a Feshbach resonance, we show that the feedback process can operate with a much higher efficiency.

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S. A. Haine, A. J. Ferris, J. D. Close, J. J. Hope. 2003-10-07. Control of an atom laser using feedback. https://doi.org/10.1103/physreva.69.013605

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