title: Universal temperature dependence, flux extinction, and the role of 3He impurities in superfluid mass transport through solid 4He.
abstract: The mass flux, F, carried by as-grown solid (4)He in the range 25.6-26.3 bar rises with falling temperature, and at a concentration-dependent temperature, T(d), the flux decreases sharply within a few mK. We study F as a function of (3)He impurity concentration, χ. We find that T(d) is an increasing function of increasing χ. At temperatures above T(d) the flux has a universal temperature dependence and the flux terminates in a narrow window near a characteristic temperature T(h) ≈ 625 mK, which is independent of χ.
authors.affiliation: Laboratory for Low Temperature Physics, Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA.
authors.forename: Ye
authors.initials: Y
authors.lastname: Vekhov
authors.affiliation: Laboratory for Low Temperature Physics, Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA.
authors.forename: W J
authors.initials: WJ
authors.lastname: Mullin
authors.affiliation: Laboratory for Low Temperature Physics, Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA.
authors.forename: R B
authors.initials: RB
authors.lastname: Hallock