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arXiv:1010.5989 · Physical Review Letters

Two-Point Phase Correlations of a One-Dimensional Bosonic Josephson Junction

Thomas Betz, Stephanie Manz, Robert Bücker, Tarik Berrada, Christian Koller, Georgy A. Kazakov, I. E. Mazets, Hans Peter Stimming, A. Perrin, Thorsten Schumm, Jörg Schmiedmayer

Published Jan 14, 2011• 95 citations
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Abstract

We realize a one-dimensional Josephson junction using quantum degenerate Bose gases in a tunable double well potential on an atom chip. Matter wave interferometry gives direct access to the relative phase field, which reflects the interplay of thermally driven fluctuations and phase locking due to tunneling. The thermal equilibrium state is characterized by probing the full statistical distribution function of the two-point phase correlation. Comparison to a stochastic model allows us to measure the coupling strength and temperature and hence a full characterization of the system.

DOI
10.1103/physrevlett.106.020407

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