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Bistability and macroscopic quantum coherence in a BEC of ^7Li

A. Montina·F. T. Arecchi
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Abstract

We consider a Bose-Einstein condensate (BEC) of $^7Li$ in a situation where the density undergoes a symmetry breaking in real space. This occurs for a suitable number of condensed atoms in a double well potential, obtained by adding a standing wave light field to the trap potential. Evidence of bistability results from the solution of the Gross-Pitaevskii equation. By second quantization, we show that the classical bistable situation is in fact a Schrödinger cat (SC) and evaluate the tunneling rate between the two SC states. The oscillation between the two states is called MQC (macroscopic quantum coherence); we study the effects of losses on MQC.

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A. Montina, F. T. Arecchi. 2002-08-12. Bistability and macroscopic quantum coherence in a BEC of ^7Li. https://doi.org/10.1103/physreva.66.013605

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