Thermodynamic studies of the orthorhombic--tetragonal transition in Ba/sub 2/YCu/sub 3/O/sub 7-//sub delta/

Journal Article · Mon Dec 26 04:00:00 EST 1988 · Appl. Phys. Lett.; (United States)

DOI:https://doi.org/10.1063/1.100553· OSTI ID:6619220

Lo, W; Tang, T B; Li, C; Xu, Y

The superconducting oxide Ba/sub 2/YCu/sub 3/O/sub 7-//sub delta/ is known to exist in two crystallographic structures, being orthorhombic or, at higher temperature, tetragonal. Thermogravimetric experiments have been performed to study their transition at different oxygen partial pressures. Weight loss curves, recorded by heating samples at various constant rates, each exhibit two inflection points. In our interpretation, such points delimit the regime within which the two structural phases coexist. Limiting values of temperature at these points, calculated by extrapolation to zero heating rates, and the corresponding magnitudes of oxygen nonstoichiometry are presented. Such data have basic significance as well as relevance to the thermal processing of materials.

• Research Organization: Physics Department, Hong Kong Baptist College, Kowloon, Hong Kong
• OSTI ID: 6619220
• Journal Information: Appl. Phys. Lett.; (United States), Journal Name: Appl. Phys. Lett.; (United States) Vol. 53:26; ISSN APPLA
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
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
CRYSTAL LATTICES
CRYSTAL STRUCTURE
CRYSTAL-PHASE TRANSFORMATIONS
ORTHORHOMBIC LATTICES
OXIDES
OXYGEN COMPOUNDS
PEROVSKITES
PHASE TRANSFORMATIONS
STOICHIOMETRY
TETRAGONAL LATTICES
THERMODYNAMICS
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
YTTRIUM OXIDES