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Josephson Junction Arrays with Bose-Einstein Condensates

F. S. Cataliotti·S. Burger·C. Fort·P. Maddaloni·F. Minardi·A. Trombettoni·A. Smerzi·M. Inguscio
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Abstract

We report on the direct observation of an oscillating atomic current in a one-dimensional array of Josephson junctions realized with an atomic Bose-Einstein condensate. The array is created by a laser standing-wave, with the condensates trapped in the valleys of the periodic potential and weakly coupled by the inter-well barriers. The coherence of multiple tunneling between adjacent wells is continuously probed by atomic interference. The square of the small-amplitude oscillation frequency is proportional to the microscopic tunneling rate of each condensate through the barriers, and provides a direct measurement of the Josephson critical current as a function of the intermediate barrier heights. Our superfluid array may allow investigation of phenomena so far inaccessible to superconducting Josephson junctions and lays a bridge between the condensate dynamics and the physics of discrete nonlinear media.

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F. S. Cataliotti, S. Burger, C. Fort, P. Maddaloni, F. Minardi, A. Trombettoni, A. Smerzi, M. Inguscio. 2001-08-07. Josephson Junction Arrays with Bose-Einstein Condensates. https://doi.org/10.1126/science.1062612

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