Irreversibility temperatures in superconducting oxides: The flux-line-lattice melting, the glass-liquid transition, or the depinning temperatures

Journal Article · Fri Mar 01 04:00:00 EST 1991 · Physical Review, B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.43.5516· OSTI ID:5845389

Xu, Y; Suenaga, M ^[1]

---

1. Division of Materials Science, Brookhaven National Laboratory, Upton, New York 11973 (US)

The magnetic-field dependence of the irreversibility temperatures follows an {ital H}={ital a}(1{minus}{ital T}{sub {ital r}}({ital H})/{ital T}{sub {ital c}}(0)){sup {ital n}} relationship with {ital n}{congruent}1.5, for pure and alloyed YBa{sub 2}(Cu{sub 1{minus}{ital x}}M{sub {ital x}}){sub 3}O{sub 7+{delta}} with {ital x}=0 and 0.02, where {ital M}=Al, Fe, Ni, and Zn, measured for an applied field parallel to the {ital c} axis. However, for {ital M}=Ni and {ital x}=0.04 and 0.06, {ital n}{congruent}2.0. This relationship is not applicable for either Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8} or (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub 10} powders. It is also shown that the irreversibility temperature is a strong function of the magnetic hysteresis width {Delta}{ital M} for pure and alloyed YBa{sub 2}Cu{sub 3}O{sub 7}. These results and the measurements of the flux creep {Delta}{ital M}({ital t}) for these specimens suggest that {ital T}{sub {ital r}}({ital H}) is a depinning line rather than a lattice melting or glass-to-liquid phase-transition temperature. However, the conventional flux-creep model cannot account for all of the observed temporal dependences of {Delta}{ital M}({ital t}).

• DOE Contract Number: AC02-76CH00016
• OSTI ID: 5845389
• Journal Information: Physical Review, B: Condensed Matter; (USA), Journal Name: Physical Review, B: Condensed Matter; (USA) Vol. 43:7; ISSN 0163-1829; ISSN PRBMD
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
ALKALINE EARTH METAL COMPOUNDS
AMORPHOUS STATE
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
HIGH-TC SUPERCONDUCTORS
HYSTERESIS
IRREVERSIBLE PROCESSES
MAGNETIC FLUX
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
SUPERCONDUCTORS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
YTTRIUM COMPOUNDS
YTTRIUM OXIDES