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Macroscopic Quantum Fluctuations in the Josephson Dynamics of Two Weakly Linked Bose-Einstein Condensates

Augusto Smerzi·Srikanth Raghavan
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Abstract

We study the quantum corrections to the Gross-Pitaevskii equation for two weakly linked Bose-Einstein condensates. The goals are: 1) to investigate dynamical regimes at the borderline between the classical and quantum behaviour of the bosonic field; 2) to search for new macroscopic quantum coherence phenomena not observable with other superfluid/superconducting systems. Quantum fluctuations renormalize the classical Josephson oscillation frequencies. Large amplitude phase oscillations are modulated, exhibiting collapses and revivals. We describe a new inter-well oscillation mode, with a vanishing (ensemble averaged) mean value of the observables, but with oscillating mean square fluctuations. Increasing the number of condensate atoms, we recover the classical Gross-Pitaevskii (Josephson) dynamics, without invoking the symmetry-breaking of the Gauge invariance.

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Augusto Smerzi, Srikanth Raghavan. 1999-07-12. Macroscopic Quantum Fluctuations in the Josephson Dynamics of Two Weakly Linked Bose-Einstein Condensates. https://doi.org/10.1103/physreva.61.063601

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