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Quantum Coherent Atomic Tunneling between Two Trapped Bose-Einstein Condensates

A. Smerzi·S. Fantoni·S. Giovanazzi·. R. Shenoy
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Abstract

We study the coherent atomic tunneling between two zero-temperature Bose-Einstein condensates (BEC) confined in a double-well magnetic trap. Two Gross-Pitaevskii equations for the self-interacting BEC amplitudes, coupled by a transfer matrix element, describe the dynamics in terms of the inter-well phase-difference and population imbalance. In addition to the anharmonic generalization of the familiar $ac$ Josephson effect and plasma oscillations occurring in superconductor junctions, the non-linear BEC tunneling dynamics sustains a self-maintained population imbalance: a novel "macroscopic quantum self-trapping effect".

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A. Smerzi, S. Fantoni, S. Giovanazzi, . R. Shenoy. 1997-06-23. Quantum Coherent Atomic Tunneling between Two Trapped Bose-Einstein Condensates. https://doi.org/10.1103/physrevlett.79.4950

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