Third sound of helium on a hydrogen substrate

Journal Article · Sun Dec 01 04:00:00 EST 1991 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.44.12453· OSTI ID:5069454

Brisson, J G; Mester, J C; Silvera, I F ^[1]

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1. Lyman Laboratory of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States)

Measurements of third sound of thin helium films on molecular-hydrogen substrates have been made as a function of the measured helium film thickness, both by a time-of-flight technique and in a third-sound resonator. Great care has been devoted to making uniform films of hydrogen, to determine reliable values of the helium-hydrogen van der Waals constant {alpha} and the thickness of the helium dead layer, {Delta}. Areal and gas-loading parameters have been measured to allow an absolute determination. We find a value of 21.3 K layer{sup 3} for {alpha} and 2.0 for {Delta}. Comparisons are made to other values in the literature. Our value of the van der Waals constant is in good agreement with a complementary determination by Paalanen and Iye and by Cieslikowski {ital et} {ital al}., using electron mobility, but is much larger than a value reported by Mochel and a value calculated by Cheng {ital et} {ital al}. We also determine values for helium on copper; however, this determination depends on the literature value for the van der Waals parameter for helium on glass.

• DOE Contract Number: FG02-85ER45190
• OSTI ID: 5069454
• Journal Information: Physical Review, B: Condensed Matter; (United States), Journal Name: Physical Review, B: Condensed Matter; (United States) Vol. 44:22; ISSN PRBMD; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

665420* -- Superfluidity-- (1992-)
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
DISPERSION RELATIONS
ELEMENTS
FILM FLOW
FLUID FLOW
FLUIDS
GASES
HELIUM
NONMETALS
RARE GASES
SUBSTRATES
SUPERFLUIDITY
THIRD SOUND
TIME-OF-FLIGHT METHOD
VAN DER WAALS FORCES