Kosterlitz-Thouless transition in helium films

G. Agnolet, D. F. McQueeney, J. D. Reppy
1989 Physical Review B (Condensed Matter)  
The superAuid response of helium Alms with transition temperatures ranging from 70 mK to 0.5 K has been studied using a torsional oscillator technique. A detailed analysis of the background indicates that the initial nonsuperAuid layer has an unexpected temperature-dependent period shift and dissipation. The superfluid response obeys a general scaling law which can be derived from the Kosterlitz-Thouless theory. Comparisons with the dynamic theory reveal nonuniversal behavior as a function of
more » ... as a function of coverage.
doi:10.1103/physrevb.39.8934 pmid:9947620 fatcat:4k77llxxkbbilk7cgi7lkqy6ni