Abstract
Motivated by many recent experimental studies of nonclassical 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<a) subtending an angle β, with 0≤β≤2π. The case β=2π corresponds to a blocked ring. We discuss the methodology to compute the NCRI effects and calculate these effects both for small angular velocities, when no vortices are present, and in the presence of a vortex. We find that, for a blocked ring, the NCRI effect is small and that therefore there will be a large discontinuity in the moment of inertia associated with blocking or unblocking circular paths. For blocked wedges (b=0) with β>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 any nonzero value of the angular velocity. Implications of our results for experiments on "supersolid" behavior in solid He4 are discussed. A number of mathematical issues are pointed out and resolved.
Original language | English (US) |
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Article number | 016303 |
Journal | Physical Review E - Statistical, Nonlinear, and Soft Matter Physics |
Volume | 79 |
Issue number | 1 |
DOIs | |
State | Published - Jan 5 2009 |