Upper critical field and normal-state properties of single-phase Y sub 1 minus x Pr sub x Ba sub 2 Cu sub 3 O sub 7 minus. delta. compounds

Journal Article · Fri Sep 01 00:00:00 EDT 1989 · Physical Review (Section) B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.40.4517· OSTI ID:5650475

Peng, J L; Klavins, P; Shelton, R N ^[1]; Radousky, H B; Hahn, P A; Bernardez, L ^[2]

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1. Department of Physics, University of California, Davis, Davis, California 95616 (US)
2. Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94550

Substitution of Pr for Y in the Y{sub 1{minus}{ital x}}Pr{sub {ital x}}Ba{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} system depresses {ital T}{sub {ital c}}, with superconductivity disappearing for {ital x}{ge}0.5. The origin of this {ital T}{sub {ital c}} depression is still controversial, as is the valence state of the Pr ion. In order to study these problems, single-phase materials were prepared with {ital x}=0.0, 0.1, 0.2, 0.3, 0.35, 0.4 0.45, 0.5, 0.6, 0.7, 0.9, and 1.0. Under certain annealing conditions, these types of samples will phase separate into YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} and Y{sub 1{minus}{ital x}}Pr{sub {ital x}}Ba{sub 2}Cu{sub 3}O{sub 7{minus}{delta}}, showing two transitions in the magnetization, but will still appear single phase from x-ray diffraction. We have overcome this problem through specific annealing conditions of time, temperature, and atmosphere. We find that the superconductivity is strongly suppressed as a function of Pr concentration, with a behavior which is consistent with the classical Abrikosov-Gor'kov pair-breaking theory. The critical fields versus {ital T} show a bell''-shaped behavior, which is consistent with the presence of magnetic pair-breaking interactions. The measured temperature dependence of the critical field, {ital H}{sub {ital c}2} near {ital T}{sub {ital c}}, and the Pauli susceptibility, are used to estimate the physical parameters {lambda}{sub GL}, {xi}{sub GL}, and {gamma}.

• DOE Contract Number: W-7405-ENG-48
• OSTI ID: 5650475
• Journal Information: Physical Review (Section) B: Condensed Matter; (USA), Vol. 40:7; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BARIUM OXIDES
CRITICAL FIELD
COPPER OXIDES
PRASEODYMIUM OXIDES
YTTRIUM OXIDES
ANNEALING
MAGNETIZATION
QUANTITY RATIO
SUPERCONDUCTIVITY
TEMPERATURE DEPENDENCE
TRANSITION TEMPERATURE
X-RAY DIFFRACTION
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
CHALCOGENIDES
COHERENT SCATTERING
COPPER COMPOUNDS
DIFFRACTION
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
HEAT TREATMENTS
MAGNETIC FIELDS
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
PRASEODYMIUM COMPOUNDS
RARE EARTH COMPOUNDS
SCATTERING
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
360204* - Ceramics
Cermets
& Refractories- Physical Properties
656100 - Condensed Matter Physics- Superconductivity