Thermopower of zinc-doped Y-Ba-Cu-O

Journal Article · Sun Oct 01 04:00:00 EDT 1989 · Physical Review (Section) B: Condensed Matter; (USA)

DOI:https://doi.org/10.1103/PhysRevB.40.6850· OSTI ID:5375662

Radhakrishnan, V ^[1]; Subramaniam, C K; Sankaranarayanan, V ^[2]; Subba Rao, G V ^[3]; Srinivasan, R ^[4]

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1. Low Temperature Laboratory, Department of Physics, Indian Institute of Technology, Madras 600036, India (IN) Material Science Research Center, Indian Institute of Technology, Madras 600036, India
2. Low Temperature Laboratory, Department of Physics, Indian Institute of Technology, Madras 600036, India
3. Material Science Research Center, Indian Institute of Technology, Madras 600036, India
4. Low Temperature Laboratory, Department of Physics, Indian Institute of

Absolute thermopower measurements on well oxygen annealed YBa{sub 2}Cu{sub 3{minus}{ital x}}Zn{sub {ital x}}O{sub 7{minus}{ital y}} ({ital x}=0.025, 0.05, 0.075, 0.1, 0.15, 0.2, 0.3, and 0.4) were made in the temperature range 250 K to the superconducting transition temperature, {ital T}{sub {ital c}} (zero). X-ray analysis showed the specimens to be single phase. The {ital T}{sub {ital c}} decreased drastically with increasing zinc concentration. The thermopower was found to be positive and an enhancement relative to the linear electron-diffusion contribution was observed over a range of temperatures from 125 K down to the onset of the superconducting transition temperature, {ital T}{sub {ital c}} (onset). The enhancement showed a steep exponential drop as the temperature increases from {ital T}{sub {ital c}} (onset). There exists unambiguous evidence that phonon drag is not responsible for the peak. The enhancement of thermopower in all these specimens varies more steeply with temperature than what one would expect from electron-phonon interaction. Hence, the cause of the enhancement must be other than the electron-phonon interaction.

• OSTI ID: 5375662
• Journal Information: Physical Review (Section) B: Condensed Matter; (USA), Journal Name: Physical Review (Section) B: Condensed Matter; (USA) Vol. 40:10; ISSN PRBMD; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
ALKALINE EARTH METAL COMPOUNDS
ALLOYS
BARIUM COMPOUNDS
BARIUM OXIDES
CHALCOGENIDES
COPPER COMPOUNDS
COPPER OXIDES
ELECTRICAL PROPERTIES
ELECTRON-PHONON COUPLING
LOW TEMPERATURE
OXIDES
OXYGEN COMPOUNDS
PHYSICAL PROPERTIES
TEMPERATURE DEPENDENCE
THERMOELECTRIC PROPERTIES
TRANSITION ELEMENT COMPOUNDS
YTTRIUM COMPOUNDS
YTTRIUM OXIDES
ZINC ADDITIONS
ZINC ALLOYS