Superfluid phase transitions in sup 3 He- sup 4 He films

Thesis/Dissertation · Fri Jan 01 04:00:00 EST 1988

OSTI ID:5596651

Wang, Xingwu

Several physical properties of {sup 3}He-{sup 4}He film were studied by means of a torsional oscillator with a Mylar substrate. The main object of the study was to verify that in some mixture films the transition to the full superfluid state can occur in two steps. Two transitions are labeled as A and B. Transition A is similar to the single transition in other mixture films. Transition B behaves somewhat differently. Nevertheless, both of A and B possess the characteristics of a Kosterlitz and Thouless transition, i.e. a sharp superfluid jump and dissipation peak. Phase A contains a larger portion of superfluid than B. The intermediate region between one and two transitions was also observed. From all of the data, the author concludes that two superfluid transitions exist in some mixture films. The total coverage of {sup 4}He and {sup 3}He should be somewhere between one and two layers in order to observe such a phenomenon. A phase diagram calculated by Mon and Saam can be used to explain the authors results, at least qualitatively. A mesa model proposed by Guyer seems closer to the experimental observation and explains the structure of the two phases.

• Research Organization: State Univ. of New York, Buffalo, NY (USA)
• OSTI ID: 5596651
• Country of Publication: United States
• Language: English

Related Subjects

640450* -- Fluid Physics-- Superfluidity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
DISPERSIONS
EVEN-EVEN NUCLEI
EVEN-ODD NUCLEI
FILMS
HELIUM 3
HELIUM 4
HELIUM ISOTOPES
ISOTOPES
LIGHT NUCLEI
MIXTURES
NUCLEI
PHASE TRANSFORMATIONS
STABLE ISOTOPES
SUPERFLUIDITY
THIN FILMS