Torsion pendulum studies of thin He-3 slabs

摘要

A high precision torsional oscillator has been developed for the detection of two dimensional superfluidity in He-3 films of thickness comparable to the superfluid coherence length, 70 nm at T = 0. The mass loading from such a film can be detected with a 0.1% resolution. Measurements on normal films show an unexpected de-coupling from the surface with decreasing temperature, below 60 mK. The frequency shift and dissipation data can be interpreted using a phenomenological interfacial friction model. (C) 2002 Elsevier Science B.V. All rights reserved. [References: 3]