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Oscillatory decay of a two-component Bose-Einstein condensate

Sigmund Kohler·Fernando Sols
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Abstract

We study the decay of a two-component Bose-Einstein condensate with negative effective interaction energy. With a decreasing atom number due to losses, the atom-atom interaction becomes less important and the system undergoes a transition from a bistable Josephson regime to the monostable Rabi regime, displaying oscillations in phase and number. We study the equations of motion and derive an analytical expression for the oscillation amplitude. A quantum trajectory simulation reveals that the classical description fails for low emission rates, as expected from analytical considerations. Observation of the proposed effect will provide evidence for negative effective interaction.

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Sigmund Kohler, Fernando Sols. 2001-07-27. Oscillatory decay of a two-component Bose-Einstein condensate. https://doi.org/10.1103/physrevlett.89.060403

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