Raman scattering from Ba/sub 2/YCu/sub 3/O/sub 7/ above and below the 90-K superconducting transition: Evidence for oxygen vacancies in the Cu-O chains

Journal Article · Sat Aug 01 04:00:00 EDT 1987 · Phys. Rev. B: Condens. Matter; (United States)

DOI:https://doi.org/10.1103/PhysRevB.36.2283· OSTI ID:6324740

Iqbal, Z; Steinhauser, S W; Bose, A; Cipollini, N; Eckhardt, H

Raman scattering data from different types of samples of the normal and superconducting phases of Ba/sub 2/YCu/sub 3/O/sub 7/ (T/sub c/approx. =90 K) and Ba/sub 2/Y/sub 0.75/Sc/sub 0.25/Cu/sub 2.4/Ni/sub 0.6//sup +2/O/sub 7/ (T/sub c/approx. =65 K) are reported and assigned. A Raman line observed at 632 cm/sup -1/ is assigned to the stretching mode of the Cu-O chains. This mode is Raman inactive in the ordered O-deficient lattice but appears to be activated by oxygen vacancies along the chains. Another sample-dependent line is observed at 365 cm/sup -1/ which gains intensity below 150 K but disappears in the superconducting phase. In the Ni-alloyed material the Raman results suggest that the Ni/sup 2+/ ions primarily occupy Cu sites in the Cu-O chains.

• Research Organization: Allied-Signal Inc., Corporate Technology, Morristown, New Jersey 07960
• OSTI ID: 6324740
• Journal Information: Phys. Rev. B: Condens. Matter; (United States), Journal Name: Phys. Rev. B: Condens. Matter; (United States) Vol. 36:4; 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
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
CHARGED PARTICLES
CHEMICAL COMPOSITION
COHERENT SCATTERING
COPPER COMPOUNDS
COPPER OXIDES
CRYSTAL DEFECTS
CRYSTAL LATTICES
CRYSTAL STRUCTURE
DIFFRACTION
ELECTRIC CONDUCTIVITY
ELECTRICAL PROPERTIES
ELEMENTS
HEAT TREATMENTS
IONS
NICKEL IONS
NONMETALS
ORTHORHOMBIC LATTICES
OXIDES
OXYGEN
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
POINT DEFECTS
POWDERS
RAMAN EFFECT
SCANDIUM IONS
SCATTERING
SUPERCONDUCTIVITY
TEMPERATURE DEPENDENCE
THERMODYNAMIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
TRANSITION TEMPERATURE
VACANCIES
X-RAY DIFFRACTION
YTTRIUM COMPOUNDS
YTTRIUM OXIDES