Critical scaling properties at the superfluid transition of 4He in aerogel
2006 (English)In: Physical Review Letters, ISSN 0031-9007, E-ISSN 1079-7114, Vol. 97, no 22Article in journal (Refereed) Published
We study the superfluid transition of 4He in aerogel by Monte Carlo simulations and finite size scaling analysis. Aerogel is a highly porous silica glass, which we model by a diffusion limited cluster aggregation model. The superfluid is modeled by a three dimensional XY model, with excluded bonds to sites on the aerogel cluster. We obtain the correlation length exponent ν=0.73±0.02, in reasonable agreement with experiments and with previous simulations. For the heat capacity exponent α, both experiments and previous simulations suggest deviations from the Josephson hyperscaling relation α=2-dν. In contrast, our Monte Carlo results support hyperscaling with α=-0.2±0.05. We suggest a reinterpretation of the experiments, which avoids scaling violations and is consistent with our simulation results.
Place, publisher, year, edition, pages
2006. Vol. 97, no 22
Research subject Fysik
IdentifiersURN: urn:nbn:se:ltu:diva-3389DOI: 10.1103/PhysRevLett.97.225702Local ID: 13640110-e6bd-11db-8a98-000ea68e967bOAI: oai:DiVA.org:ltu-3389DiVA: diva2:976247
Validerad; 2006; Bibliografisk uppgift: Paper id:: 225702; 20061214 (weber)2016-09-292016-09-29Bibliographically approved