Nucleation and interfacial coupling between pure and dirty superfluid phases of 3He.
The nucleation of the first-order phase transition of superfluid 3He-B from superfluid 3He-A is quite remarkable since it requires a seed of the order of a micron. We have studied this nucleation for 3He confined to a very dilute silica aerogel. This dirty superfluid behaves in a manner similar to previous reports for the pure superfluid. But we have discovered a novel magnetically driven nucleation switch acting on the pure superfluid- B phase. Last, we find the surprising result that the proximity effect between the pure and dirty superfluids at their interface is insufficient to nucleate the B phase in either superfluid.
Gervais
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G
Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208, USA.
Yawata
K
K
Mulders
N
N
Halperin
W P
WP