Reversal of the circulation of a vortex by quantum tunneling in trapped Bose systems
- Niels Bohr Institute, Blegdamsvej 17, DK-2100 Copenhagen O (Denmark)
We study the quantum dynamics of a model for a vortex in a Bose gas with repulsive interactions in an anisotropic, harmonic trap. By solving the Schroedinger equation numerically, we show that the circulation of the vortex can undergo periodic reversals by quantum-mechanical tunneling. With increasing interaction strength or particle number, vortices become increasingly stable, and the period for reversals increases. Tunneling between vortex and antivortex states is shown to be described to a good approximation by a superposition of vortex and antivortex states (Schroedinger cat state), rather than the mean-field state, and we derive an analytical expression for the oscillation period. The problem is shown to be equivalent to that of the two-site Bose-Hubbard model with attractive interactions.
- OSTI ID:
- 21011363
- Journal Information:
- Physical Review. A, Vol. 76, Issue 2; Other Information: DOI: 10.1103/PhysRevA.76.021605; (c) 2007 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA); ISSN 1050-2947
- Country of Publication:
- United States
- Language:
- English
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