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arXiv · 0810.0307

Quantum switching at a mean-field instability of a Bose-Einstein condensate in an optical lattice

V. S. Shchesnovich·V. V. Konotop
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Abstract

It is shown that bifurcations of the mean-field dynamics of a Bose-Einstein condensate can be related with the quantum phase transitions of the original many-body system. As an example we explore the intra-band tunneling in the two-dimensional optical lattice. Such a system allows for easy control by the lattice depth as well as for macroscopic visualization of the phase transition. The system manifests switching between two selftrapping states or from a selftrapping state to a superposition of the macroscopically populated selftrapping states with the step-like variation of the control parameter about the bifurcation point. We have also observed the magnification of the microscopic difference between the even and odd number of atoms to a macroscopically distinguishable dynamics of the system.

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V. S. Shchesnovich, V. V. Konotop. 2009-01-10. Quantum switching at a mean-field instability of a Bose-Einstein condensate in an optical lattice. https://doi.org/10.1103/physrevlett.102.055702

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