Diffusion of oxygen in superconducting YBa/sub 2/Cu/sub 3/O/sub 7-//sub delta/ ceramic oxides

Journal Article · Sun Jan 01 04:00:00 EST 1989 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.39.304· OSTI ID:6552117

Tu, K N; Yeh, N C; Park, S I; Tsuei, C C

We have used in situ resistivity measurements to monitor the diffusion of oxygen in and out of the ceramic oxide YBa/sub 2/Cu/sub 3/O/sub 7-//sub delta/. The study of out diffusion of oxygen was carried out by annealing the oxide in ambient helium at constant heating rates and at constant temperatures. The rate of out diffusion of oxygen has been found to be independent of delta, and the resistivity changes linearly with time during isothermal anneals. Assuming that the rate of out diffusion is surface reaction limited, we have determined a surface barrier of 1.7 eV. The study of in diffusion of oxygen was performed by annealing the oxygen-deficient oxide (delta = 0.38) in ambient oxygen. The in diffusion rate was found to depend strongly on delta; we have determined the activation energies of the process at delta = 0.38 and delta = 0 to be 0.5 eV and 1.3 eV, respectively. The diffusivity of oxygen for delta = 0 has been determined to be D = 0.035 exp(-1.3 eV)/ kT) cm/sup 2//sec. Combining the kinetic data and published structural information, we have examined a vacancy mechanism and a twinning mechanism for anisotropic diffusion of oxygen in the CuO layer between the BaO layers.

• Research Organization: IBM Research Division, Thomas J. Watson Research Center, Yorktown Heights, New York 10598
• OSTI ID: 6552117
• 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

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
656100 -- Condensed Matter Physics-- Superconductivity
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
ALKALINE EARTH METAL COMPOUNDS
ANISOTROPY
ATOM TRANSPORT
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COHERENT SCATTERING
COPPER COMPOUNDS
COPPER OXIDES
CRYSTAL DEFECTS
CRYSTAL STRUCTURE
DIFFRACTION
DIFFUSION
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELECTRON MICROSCOPY
ELEMENTS
LOW TEMPERATURE
MEDIUM TEMPERATURE
MICROSCOPY
NEUTRAL-PARTICLE TRANSPORT
NONMETALS
OXIDES
OXYGEN
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
POINT DEFECTS
RADIATION TRANSPORT
SCANNING ELECTRON MICROSCOPY
SCATTERING
SUPERCONDUCTORS
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
VACANCIES
X-RAY DIFFRACTION
YTTRIUM COMPOUNDS
YTTRIUM OXIDES