Flux-creep studies of vortex pinning in an aligned YBa sub 2 Cu sub 3 O sub 7 minus. delta. superconductor with oxygen deficiencies. delta. le 0. 2

Journal Article · Sat Aug 01 00:00:00 EDT 1992 · Physical Review, B: Condensed Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.46.3050· OSTI ID:7039729

Ossandon, J G ^[1]; Thompson, J R ^[2]; Christen, D K; Sales, B C ^[3]; Sun, Y ^[1]; Lay, K W ^[4]

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1. Department of Physics, University of Tennessee, Knoxville, Tennessee 37996-1200 (United States)
2. Solid State Division, Oak Ridge National Laboratory, Building 3115, P.O. Box 2008, Oak Ridge, Tennessee 37831-6061 (United States) Department of Physics, University of Tennessee, Knoxville, Tennessee 37996-1200 (United States)
3. Solid State Division, Oak Ridge National Laboratory, Building 3115, P.O. Box 2008, Oak Ridge, Tennessee 37831-6061 (United States)
4. General Electric Corporate Research and Development Center, Schenectady, New York 12301 (United States)

Flux-creep measurements were carried out in magnetically aligned, sintered samples of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} with various oxygen deficiencies {delta} (in the range 0{le}{delta}{le}0.2), for temperatures {ital T} in the range from 5 to 75 K, with an applied magnetic field {bold H}{parallel}{ital c} axis of 1 T. The normalized flux-creep rate {ital S}={ital d} ln{ital M}/{ital d} ln{ital t} was determined as a function of {ital T} and {delta}. The effective vortex-pinning potential {ital U}{sub eff}({ital J}) and the pinning energy {ital U}{sub 0} were calculated both in the linear Anderson-Kim approximation as well as in the nonlinear formalism of vortex-glass and collective-pinning theory. The applicability of the nonlinear formalism was tested and discussed. There is a close correspondence between the energy scaling parameter {ital U}{sub 0} of the nonlinear model and the pinning energy of a pointlike pinning center. A comparison of the experimental results with predictions of collective-pinning theory reveals a consistent picture of vortex motion in this family of superconductors.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 7039729
• Journal Information: Physical Review, B: Condensed Matter; (United States), Vol. 46:5; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM OXIDES
MAGNETIC FLUX
COPPER OXIDES
YTTRIUM OXIDES
CREEP
HIGH-TC SUPERCONDUCTORS
SINTERED MATERIALS
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
CHALCOGENIDES
COPPER COMPOUNDS
MATERIALS
MECHANICAL PROPERTIES
OXIDES
OXYGEN COMPOUNDS
SUPERCONDUCTORS
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
360207* - Ceramics
Cermets
& Refractories- Superconducting Properties- (1992-)