Electron-lattice coupling and stripe formation in La{sub 2{minus}x}Ba{sub x}CuO{sub 4}

Journal Article · Mon Sep 01 00:00:00 EDT 1997 · Physical Review, B: Condensed Matter

DOI:https://doi.org/10.1103/PhysRevB.56.6288· OSTI ID:542252

Zhou, J; Goodenough, J B ^[1]

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1. Center for Materials Science Engineering, ETC 9.102, University of Texas at Austin, Austin, Texas 78712-1063 (United States)

The temperature dependence of the resistance R(T) and the thermoelectric power {alpha}(T) under different hydrostatic pressures P are reported for polycrystalline La{sub 2{minus}x}Ba{sub x}CuO{sub 4}, 0.11{le}x{le}14; they reveal a minimum in R(T) and an abrupt change in the sign of {alpha}(T) at a transition from the low-temperature tetragonal (LTT) to the low-temperature orthorhombic phase. Superconductivity is suppressed at ambient pressure in the range 0.12{le}x{le}0.13, where neutron-diffraction data have shown a static charge ordering into hole-rich and magnetic stripes, but pressure introduces n-type superconductivity into these compositions within the LTT phase with a dT{sub 0}/dP{approx}1.0K/kbar. The x=0.14 sample is superconductive at ambient pressure in the LTT phase, and dT{sub 0}/dP{gt}0 changes to dT{sub 0}/dP=0 at a P{sub c}{approx}10kbar. No anomaly in the transport properties is found at the magnetic ordering temperature T{sub N}{approx}30K in the LTT phase. These data, which show no support for stripe formation and superconductivity resulting from magnetic interactions, are found to be compatible with a model of strong coupling of charge carriers in coherent electronic states to fluctuations in the Cu-O bond lengths. Periodically alternating stripes of hole-rich and magnetic domains in the CuO{sub 2} sheets are pinned, for x{approx}1/8, by the crystallographic distortion of the LTT phase; but the application of hydrostatic pressure, which decreases the magnitude of the LTT deformation, restores superconductivity apparently by depinning the stripes. {copyright} {ital 1997} {ital The American Physical Society}

• OSTI ID: 542252
• Journal Information: Physical Review, B: Condensed Matter, Journal Name: Physical Review, B: Condensed Matter Journal Issue: 10 Vol. 56; ISSN PRBMDO; ISSN 0163-1829
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
66 PHYSICS
BARIUM COMPOUNDS
BARIUM OXIDES
BOND LENGTHS
COPPER OXIDES
ELECTRIC CONDUCTIVITY
ELECTRIC IMPEDANCE
HIGH-TC SUPERCONDUCTORS
LANTHANUM COMPOUNDS
LANTHANUM OXIDES
PRESSURE DEPENDENCE
TEMPERATURE DEPENDENCE
THERMOELECTRIC PROPERTIES