Raman spectra, superconductivity, and structure of Co-substituted YBa sub 2 Cu sub 3 O sub 7 minus. delta

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

DOI:https://doi.org/10.1103/PhysRevB.40.6787· OSTI ID:5375275

Kakihana, M; Borjesson, L ^[1]; Eriksson, S ^[2]; Svedlindh, P; Norling, P ^[3]

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1. Department of Physics, Chalmers University of Technology, S-412 96 Gothenburg, Sweden (SE)
2. Department of Inorganic Chemistry, Chalmers University of Technology, S-412 96 Gothenburg, Sweden
3. Uppsala University, Institute of Technology, Box 534, S-751 21 Uppsala, Sweden

A systematic Raman spectroscopic investigation has been performed on YBa{sub 2}Cu{sub 3{minus}{ital x}}Co{sub {ital x}}O{sub 7{minus}{delta}} ceramic samples of different Co content {ital x} in the interval 0{le}{ital x}{le}0.6. The structure and the superconducting properties of the samples have been carefully characterized by x-ray diffraction, magnetic susceptibility, and resistivity measurements. It is found that the frequency of the axial stretching vibration of O(4) at 502 cm{sup {minus}1} decreases, the frequency of the Cu(2)-O(2),O(3) in-phase bending vibration at 440 cm{sup {minus}1} increases, and the frequency of the Cu(2)-O(2),O(3) out-of-phase bending vibration at 335 cm{sup {minus}1} remains constant for increasing Co concentration. The dependencies of the frequencies as well as of the intensities of these vibrational modes on cobalt substitution are reminiscent of the behavior of the corresponding modes for pure YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}} of increasing oxygen deficiency. It is proposed that the frequency of this mode is directly dependent on the free-charge carrier concentration and is sensitive to the charge balance between the chains and the planes. Moreover, the resultant changes of the vibrational modes on Co substitution provide additional evidence for the mode assignments of YBa{sub 2}Cu{sub 3}O{sub 7{minus}{delta}}

• OSTI ID: 5375275
• Journal Information: Physical Review (Section) B: Condensed Matter; (USA), Vol. 40:10; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
BARIUM OXIDES
PHYSICAL PROPERTIES
COBALT OXIDES
COPPER OXIDES
YTTRIUM OXIDES
CARRIER DENSITY
CRYSTAL STRUCTURE
ELECTRIC CONDUCTIVITY
FREQUENCY DEPENDENCE
MAGNETIC SUSCEPTIBILITY
OSCILLATION MODES
QUANTITY RATIO
RAMAN SPECTRA
SUPERCONDUCTIVITY
X-RAY DIFFRACTION
ALKALINE EARTH METAL COMPOUNDS
BARIUM COMPOUNDS
CHALCOGENIDES
COBALT COMPOUNDS
COHERENT SCATTERING
COPPER COMPOUNDS
DIFFRACTION
ELECTRICAL PROPERTIES
MAGNETIC PROPERTIES
OXIDES
OXYGEN COMPOUNDS
SCATTERING
SPECTRA
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
360204* - Ceramics
Cermets
& Refractories- Physical Properties
656100 - Condensed Matter Physics- Superconductivity