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arXiv · 0812.3112

Hydrodynamics of superfluids confined in blocked rings and wedges

Chandan Dasgupta·Oriol T. Valls
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Abstract

Motivated by many recent experimental studies of non-classical rotational inertia (NCRI) in superfluid and supersolid samples, we present a study of the hydrodynamics of a superfluid confined in the two-dimensional region (equivalent to a long cylinder) between two concentric arcs of radii $b$ and $a$ ($b π$, we find an unexpected divergence of the velocity at the origin, which implies the presence of either a region of normal fluid or a vortex for {\it any} nonzero value of the angular velocity. Implications of our results for experiments on "supersolid" behavior in solid $^4{\rm He}$ are discussed. A number of mathematical issues are pointed out and resolved.

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Chandan Dasgupta, Oriol T. Valls. 2008-12-16. Hydrodynamics of superfluids confined in blocked rings and wedges. https://doi.org/10.1103/physreve.79.016303

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