2007/08/31 by Chaohong Lee, Libin Fu, Yuri S. Kivshar · 1 citation
Computer Science · Physics and Astronomy · #Atomic and Subatomic Physics Research #Cold Atom Physics and Bose-Einstein Condensates #Quantum Information and Cryptography #quant-ph
paper · pdf · doi:10.1209/0295-5075/81/60006
published as EPL, 81 (2008) 60006 · 6 pages, 5 figures, accepted for publication in EPL (Europhysics Letters)
arxiv created 2008/02/01 · openalex publication_date 2008/03/01 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/30
We study many-body quantum coherence and interaction blockade in two Josephson-linked Bose-Einstein condensates. We introduce universal operators for characterizing many-body coherence without limitations on the system symmetry and total particle number N . We reproduce the results for both coherence fluctuations and number squeezing in symmetric systems of large N , and reveal several peculiar phenomena that may occur in asymmetric systems and systems of small N . For asymmetric systems, we show that, due to an interplay between asymmetry and inter-particle interaction, the coherence fluctuations are suppressed dramatically when | E C / E J |≪1, and both resonant tunneling and interaction blockade take place for large values of | E C / E J |, where E C and E J are the interaction and tunneling energies, respectively. We emphasize that the resonant tunneling and interaction blockade may allow creating single-atom devices with promising technology applications. We demonstrate that for the systems at finite temperatures the formation of self-trapped states causes an anomalous behavior.