Ultrasonic measurements on superconducting UPt sub 3 and superfluid sup 3 He

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6053873

Adenwalla, S

The author presents ultrasonic measurements on two highly correlated systems, UPt{sub 3} and {sup 3}He. He has measured the ultrasonic attenuation in superconducting UPt{sub 3} as a function of field and temperature. An anomalous peak has been observed in the longitudinal ultrasonic attenuation in both field and temperature sweeps. He interprets this peak as a signature of a phase transition in the mixed state of UPt{sub 3} which is strong evidence for unconventional superconductivity. He presents phase diagrams in the field-temperature plane for different orientations of field. The peak shifts to lower fields as the temperature is increased, roughly tracking H{sub c2}. The position of the peak in the field sweep is found to depend strongly on the orientation of the field relative to the c-axis. In contrast to the behavior of H{sub c2}, he finds that the phase line shifts to lower fields as the field is rotated away from the c-axis into the basal plane. The temperature dependence of the attenuation in zero field goes at T{sup 2}, unlike the expected exponential temperature dependence. The ultrasonic measurements on superfluid {sup 3}He investigated the J = 2 collective modes. He has used a new technique involving alternate pressure and temperature sweeps. The results agree reasonably well with previously collected data.

• Research Organization: Northwestern Univ., Evanston, IL (USA)
• OSTI ID: 6053873
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102 -- Metals & Alloys-- Structure & Phase Studies
360104 -- Metals & Alloys-- Physical Properties
640450* -- Fluid Physics-- Superfluidity
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ACOUSTIC TESTING
ACTINIDE ALLOYS
ALLOYS
DIAGRAMS
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
EVEN-ODD NUCLEI
HELIUM 3
HELIUM ISOTOPES
INTERMETALLIC COMPOUNDS
ISOTOPES
LIGHT NUCLEI
MATERIALS TESTING
NONDESTRUCTIVE TESTING
NUCLEI
PHASE DIAGRAMS
PHASE TRANSFORMATIONS
PHYSICAL PROPERTIES
PLATINUM ALLOYS
PLATINUM METAL ALLOYS
STABLE ISOTOPES
SUPERCONDUCTIVITY
SUPERFLUIDITY
TEMPERATURE DEPENDENCE
TESTING
ULTRASONIC TESTING
URANIUM ALLOYS