C-Axis Spectra of La<sub>2-x </sub>Ba<sub>x</sub>CuO<sub>4</sub> in the Normal and Superconducting State

ORAL

Abstract

Reflectance spectra of superconducting La2-xBaxCuO4 have been studied for polarization parallel to the c-axis in a wide frequency range from 20-35,000 cm-1, at doping from 0≤x≤0.155 and temperatures above and below Tc. The samples are single crystals grown using the traveling solvent floating zone method. These samples were wet polished with alumina fine powder to make a good reflective surface. The c-axis spectra showed insulating behavior, with only lattice vibrations below the charge-transfer gap. We observed below Tc no evidence for a Josephson plasma edge in the far infrared, despite seeing good superconducting behavior for the a-axis spectra. The results of annealing in an oxygen atmosphere will be discussed.

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Presenters

  • Vladimir Martinez

    • Department of Physics, Univeristy of Florida, Gainesville, FL, USA, 32611

Authors

  • Vladimir Martinez

    • Department of Physics, Univeristy of Florida, Gainesville, FL, USA, 32611

  • Luyi Yan

    • Department of Physics, Univeristy of Florida, Gainesville, FL, USA, 32611

  • David Tanner

    • Department of Physics, Univeristy of Florida, Gainesville, FL, USA, 32611

  • Genda Gu

    • Brookhaven National Laboratory
    • Brookhaven National Lab
    • Department of Condensed Matter Physics and Materials Science, Brookhaven, Brookhaven National Laboratory, Upton, New York 11973-5000, USA.
    • Cond. Matt. Physics and Material Science, Brookhaven Natl Lab
    • Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory
    • Condensed Matter Physics & Materials Science Department, Brookhaven National Laboratory
    • Brookhaven National Labs, Long Island, NY, USA, 11973
    • Condensed Matter Physics & Materials Science, Brookhaven National Laboratory
    • Condensed Matter Physics, Brookhaven National Laboratory
    • Brookhaven National Laboratories
    • Chinese Academy of Sciences
    • Condensed Matter Physics & Materials Science, Brookhaven National Lab
    • Brookhaven Natl Lab