Accession Number:

ADA190417

Title:

Thin Superconducting Film Characterization by Surface Acoustic Waves

Descriptive Note:

Annual progress rept. 30 Sep 86-30 Sep 87

Corporate Author:

WISCONSIN UNIV-MADISON DEPT OF PHYSICS

Personal Author(s):

Report Date:

1987-10-30

Pagination or Media Count:

15.0

Abstract:

A dilution refrigerator was installed tested and modified. Several cryogenic probes were fabricated to measure resistivity, ac susceptibility and ultrasonic attenuation in high T superconductors. Ultrasonic attenuation measurements were performed on single crystals of UPt3 and URu2Si2. A maximum in attenuation was found below the superconducting transition temperature TC of URu2Si2. A magnetic field decreased this maximum. The temperature of the attenuation in the normal and superconducting states below Tc was measured in UPt3. The ratio of the attenuation follows a power law dependence indicative of an anisotropic superconducting energy gap. A peak in attenuation was found in the mixed state of UPt3, which may be associated with a phase transition of the flux line lattice.

Subject Categories:

  • Thermodynamics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE