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Observation of harmonic generation and nonlinear coupling in the collective dynamics of a Bose condensate

G. Hechenblaikner·O. M. Marago'·E. Hodby·J. Arlt·S. Hopkins·C. J. Foot
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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 TOP 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.

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G. Hechenblaikner, O. M. Marago', E. Hodby, J. Arlt, S. Hopkins, C. J. Foot. 2000-03-30. Observation of harmonic generation and nonlinear coupling in the collective dynamics of a Bose condensate. https://doi.org/10.1103/physrevlett.85.692

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