Shape Oscillations in Levitated He II Drops
We describe experiments to study the shape oscillations of levitated He II drops. Drops of approximately 0.5 cm diameter are levitated magnetically with a superconducting solenoid, and shape oscillations are induced with an ac electric field. We have measured the damping of shape oscillations as a function of temperature. The damping rate is compared to that predicted by a two fluid, hydrodynamic model, which takes account the effect of the motion in the vapor. The effects of condensation and evaporation on the motion of the drop are also considered.
KeywordsEvaporation Magnetic Material Hydrodynamic Model Superconducting Solenoid Shape Oscillation
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