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arXiv:cond-mat/0003495 · Physical Review Letters

Observation of Harmonic Generation and Nonlinear Coupling in the Collective Dynamics of a Bose-Einstein Condensate

Gerald Hechenblaikner, Onofrio M. Maragò, E. Hodby, J. Arlt, S. A. Hopkins, Christopher J. Foot

Published Jul 24, 2000• 53 citations
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Abstract

We report the observation of harmonic generation and strong nonlinear coupling of two collective modes of a condensed gas of rubidium atoms. Using a modified time averaged orbiting potential trap we changed the trap anisotropy to a value where the frequency of the m = 0 high-lying mode corresponds to twice the frequency of the m = 0 low-lying mode, thus leading to strong nonlinear coupling between these modes. By changing the anisotropy of the trap and exciting the low-lying mode we observed significant frequency shifts of this fundamental mode and also the generation of its second harmonic.

DOI
10.1103/physrevlett.85.692

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