Pressure dependence of thermopower in YBa{sub 2}Cu{sub 3}O{sub 6.96} and YBa{sub 2}Cu{sub 4}O{sub 8}

Journal Article · Tue Apr 30 20:00:00 EDT 1996 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.53.R11976· OSTI ID:283926

Zhou, J; Goodenough, J B ^[1]

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1. Center for Materials Science and Engineering, ETC 9.102, University of Texas at Austin, Austin, Texas 78712 (United States)

Measurements of the temperature dependencies of the thermopower {alpha}({ital T}) and the resistivity {rho}({ital T}) of polycrystalline YBa{sub 2}Cu{sub 3}O{sub 6.96} and YBa{sub 2}Cu{sub 4}O{sub 8} under different hydrostatic pressures are reported. They are interpreted to reveal an increase with pressure in the superconductive-condensate density {ital n}{sub {ital s}} of the chains. A literature report of {ital dT}{sub {ital c}}/{ital dP}=0.25 K/kbar for optimally doped Y{sub 0.9}Ca{sub 0.1}Ba{sub 2}Cu{sub 4}O{sub 8} is argued to be due to an increase in the elastic coupling between the CuO{sub 2} sheets of the double Cu-O chains as a result of the increase in chain {ital n}{sub {ital s}}. A {ital c}-axis in-phase {ital A}{sub {ital g}} vibration of the oxygen atoms of the CuO{sub 2} sheets is identified as a participant in the underlying physical mechanism responsible not only for high-{ital T}{sub {ital c}} superconductivity, but also for the pressure dependencies of {ital T}{sub {ital c}} and {alpha}({ital T}). {copyright} {ital 1996 The American Physical Society.}

• OSTI ID: 283926
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 18 Vol. 53; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
BARIUM OXIDES
COPPER OXIDES
ELECTRIC CONDUCTIVITY
ELECTRON TRANSFER
ELECTRONIC STRUCTURE
HIGH-TC SUPERCONDUCTORS
PRESSURE DEPENDENCE
TEMPERATURE DEPENDENCE
TEMPERATURE RANGE 0065-0273 K
THERMOELECTRIC PROPERTIES
TRANSITION TEMPERATURE
YTTRIUM OXIDES