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# Nonlinear phase dynamics in a driven bosonic Josephson junction.

Department of Chemistry, Ben-Gurion University of the Negev, Post Office Box 653, Beer-Sheva 84105, Israel.
Physical Review Letters (Impact Factor: 7.94). 06/2010; 104(24):240402. DOI:10.1103/PHYSREVLETT.104.240402
Source: PubMed

ABSTRACT We study the collective dynamics of a driven two-mode Bose-Hubbard model in the Josephson interaction regime. The classical phase space is mixed, with chaotic and regular components, which determine the dynamical nature of the fringe visibility. For a weak off-resonant drive, where the chaotic component is small, the many-body dynamics corresponds to that of a Kapitza pendulum, with the relative phase φ between the condensates playing the role of the pendulum angle. Using a master equation approach we show that the modulation of the intersite potential barrier stabilizes the φ=π "inverted pendulum" coherent state, and protects the fringe visibility.

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