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arXiv · 1109.0039

Coherent cross-talk and parametric driving of matter-wave vortices

Abstract

We show that the interaction between vortices and sound waves in atomic Bose-Einstein condensates can be elucidated in a double-well trap: with one vortex in each well, the sound emitted by each precessing vortex can be driven into the opposing vortex (if of the same polarity). This cross-talk leads to a periodic exchange of energy between the vortices which is long-range and highly efficient. The increase in vortex energy (obtained by numerical simulations of the Gross-Pitaevskii equation) is significant and experimentally observable as a migration of the vortex to higher density over just a few precession periods. Similar effects can be controllably engineered by introducing a precessing localised obstacle into one well as an artificial generator of sound, thereby demonstrating the parametric driving of energy into a vortex.

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N. G. Parker, A. J. Allen, C. F. Barenghi, N. P. Proukakis. 2011-08-31. Coherent cross-talk and parametric driving of matter-wave vortices. https://doi.org/10.1103/physreva.86.013631

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