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arXiv · 1704.01968

Dissipation in mesoscale superfluids

Adrian Del Maestro·Bernd Rosenow
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Abstract

We investigate the maximum speed at which a driven superfluid can flow through a narrow constriction with a size on the order of the healing length. Considering dissipation via the thermal nucleation of quantized vortices, we calculate the critical velocity for superfluid $^4$He and ultracold atomtronic circuits, identify fundamental length and velocity scales, and are thus able to present results obtained in widely different temperature and density ranges in a universal framework. For ultra-narrow channels we predict a drastic reduction in the critical velocity as the energy barrier for flow reducing thermally activated phase slip fluctuations is suppressed.

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Adrian Del Maestro, Bernd Rosenow. 2017-04-06. Dissipation in mesoscale superfluids. https://doi.org/10.1103/physrevb.95.140507

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