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Macroscopic Quantum Coherence in a repulsive Bose-Einstein condensate

A. Montina·F. T. Arecchi
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Abstract

We consider a Bose-Einstein bicondensate (BEC) of $^{87}Rb$, trapped in two different internal levels, in a situation where the density undergoes a symmetry breaking in momentum space. This occurs for a suitable number of condensed atoms within a double well dispersion curve, obtained by Raman coupling two internal states with two tilted and detuned light fields. Evidence of bistability results from the Gross-Pitaevskii equation. By second quantization, we evaluate the tunneling rate between the two asymmetric states; the effects of losses on coherence are also considered.

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A. Montina, F. T. Arecchi. 2002-06-04. Macroscopic Quantum Coherence in a repulsive Bose-Einstein condensate. https://doi.org/10.1103/physreva.67.023616

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