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Detecting phonons and persistent currents in toroidal Bose-Einstein condensates by means of pattern formation

M. Modugno·C. Tozzo·F. Dalfovo
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Abstract

We theoretically investigate the dynamic properties of a Bose-Einstein condensate in a toroidal trap. A periodic modulation of the transverse confinement is shown to produce a density pattern due to parametric amplification of phonon pairs. By imaging the density distribution after free expansion one obtains i) a precise determination of the Bogoliubov spectrum and ii) a sensitive detection of quantized circulation in the torus. The parametric amplification is also sensitive to thermal and quantum fluctuations.

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M. Modugno, C. Tozzo, F. Dalfovo. 2006-11-13. Detecting phonons and persistent currents in toroidal Bose-Einstein condensates by means of pattern formation. https://doi.org/10.1103/physreva.74.061601

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