Ultrasonic velocity anomalies in superconducting sinter-forged YBa/sub 2/Cu/sub 3/O/sub 7-//sub delta/
The velocity of ultrasound was measured on sinter-forged polycrystalline YBa/sub 2/Cu/sub 3/O/sub 7-//sub delta/ samples with a superconducting transition temperature of 91 K. The forging process results in crystallites which are preferentially aligned with their c axis aligned parallel to the forging axis as confirmed from optical and x-ray measurements. Sound-velocity measurements show that the material is elastically anisotropic. The temperature dependence of the sound velocity shows distinct anomalies. For propagation parallel to the forging axis, both longitudinal and shear waves displayed a thermal hysteresis between 65 and 260 K; however the longitudinal sound velocity with q-circumflex in the basal plane showed a much smaller thermal hysteresis. No effect of a magnetic field was observed on sweeping the magnetic field to 7.2 T at temperatures of 4 and 86 K.
- Research Organization:
- Department of Physics and Astronomy, Northwestern University, Evanston, Illinois 60208
- OSTI ID:
- 6441428
- Journal Information:
- Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 39:1; ISSN PRBMD
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
HYSTERESIS
LOW TEMPERATURE
MAGNETIC FIELDS
OXIDES
OXYGEN COMPOUNDS
SOUND WAVES
SUPERCONDUCTORS
TEMPERATURE DEPENDENCE
TRANSITION ELEMENT COMPOUNDS
ULTRASONIC WAVES
YTTRIUM COMPOUNDS
YTTRIUM OXIDES