Quantum tunneling and Josephson current in Bose-Einstein condensates

Sadhan K. Adhikari

Published Aug 20, 2003• 0 citations

Abstract

Using the mean-field Gross-Pitaevskii (GP) equation we study the evolution of Josephson current in a repulsive Bose-Einstein condensate in an optical-lattice potential initiated by a sudden displacement of the trapping potential. Similarly, we also study the evolution of quantum tunneling in a double-well potential in one and three dimensions initiated by a trap displacement leading to a periodic oscillation of the condensate across the barrier which could be observed experimentally. The frequencies of Josephson current found directly from the solution of the GP equation are in agreement with the experiment by Cataliotti et al. [2001 Science 293 843]. The breakdown of the Josephson current for a large trap displacement is also in agreement with another experiment by Cataliotti et al. [2003 New J. Phys. 5 71]. PACS numbers: 03.75.Lm, 03.75.KkQuantum tunneling and Josephson current in Bose-Einstein condensates 2 1.

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