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arXiv · 1803.00277

Kelvin-Helmholtz instability in an atomic superfluid

A. W. Baggaley·N. G. Parker
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Abstract

We demonstrate an experimentally feasible method for generating the classical Kelvin-Helmholtz instability in a single component atomic Bose-Einstein condensate. By progressively reducing a potential barrier between two counter-flowing channels we seed a line of quantised vortices, which precede to form progressively larger clusters, mimicking the classical roll-up behaviour of the Kelvin-Helmholtz instability. This cluster formation leads to an effective superfluid shear layer, formed through the collective motion of many quantised vortices. From this we demonstrate a straightforward method to measure the effective viscosity of a turbulent quantum fluid in a system with a moderate number of vortices, within the range of current experimental capabilities.

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BibTeXRIS

A. W. Baggaley, N. G. Parker. 2018-03-01. Kelvin-Helmholtz instability in an atomic superfluid. https://doi.org/10.1103/physreva.97.053608

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