Vibrational Density-of-States, Isotope effect, and Superconductivity in Ba1-xKxBiO3 Cubic Oxides

  • Marcos H. Degani
  • Rajiv K. Kalia
  • P. Vashishta

Abstract

Vibrational density-of-states of insulating BaBiO3 in orthorhombic phase and superconducting Ba0.6K0.4BiO3 in cubic phase are studied using the molecular dynamics (MD) method. The MD results are compared with the recent inelastic neutron scattering and electron tunneling experiments. The exponent of the oxygen isotope effect is calculated from the first moment of the phonon density-of-states (the weak coupling limit) and from the solution of Eliashberg gap equations. Results are compared with isotope effect experiments. Evidence based on inelastic neutron scattering, tunneling, and isotope effect experiments when combined with the MD calculations suggest that this material is a normal weak coupling BCS superconductor with strong coupling of the carriers to high energy oxygen phonons.

Keywords

Coherence Perovskite Autocorrelation Sera Alben 

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References

  1. 1.
    D. G. Hinks, D. R. Richards, B. Dabrowski, D. T. Marx, and A. W. Mitchell, Nature 335:419(1988).CrossRefGoogle Scholar
  2. 2.
    B. Batlogg, R. J. Cava, L. W. Rupp, Jr., A. M. Mujsce, J. P. Remeika, W. F. Peck, Jr., A. S. Cooper, and G. P. Espinosa, Phys. Rev. Lett. 61: 1670 (1987).CrossRefGoogle Scholar
  3. 3.
    S. Kondoh, M. Sera, Y. Ando and M. Sato, Physica C 157:469 (1989).CrossRefGoogle Scholar
  4. 4.
    Z. Schlesinger, R. T. Collins, J. A. Calise, D. G. Hinks, A. W. Mitchell, Y. Zheng, and B. Dabrowski, N. E. Bickers, and D. J. Scalapino, submitted to Phys. Rev. B.Google Scholar
  5. 5.
    C.-K. Loong, P. Vashishta, R. K. Kalia, M. H. Degani, D. L. Price, J. D. Jorgensen, D. G. Hinks, B. Dabrowski, A. W. Mitchell, D. R. Richards, and Y. Zheng, Phys. Rev. Lett. 62:2628 (1989).CrossRefGoogle Scholar
  6. 6.
    J. F. Zasadzinski, N. Tralshawala, D. G. Hinks, B. Dabrowski, A. W. Mitchell, D. R. Richards, Physica C 158:519 (1989).CrossRefGoogle Scholar
  7. 7.
    J. Bardeen, L. N. Cooper, and J. R. Schrieffer, Phys. Rev. 108:1175 (1957)CrossRefGoogle Scholar
  8. 8.
    S. Pei, J. D. Jorgensen, B. Dabrowski, D. G. Hinks, D. R. Richards, A. W. Mitchell, J. M. Newsam, S. K. Sinha, D. Vaknin, and A. J. Jacobson, submitted to Phys. Rev. B.Google Scholar
  9. 9.
    P. Vashishta, and A. Rahman, Phys. Rev. Lett. 40: 1337 (1978), and P. Vashishta, R. K. Kalia, and I. Ebbsjö, Phys. Rev. B 39:6034 (1988).CrossRefGoogle Scholar
  10. 10.
    M. H. Degani, R. K. Kalia, and P. Vashishta, to be published.Google Scholar
  11. 11.
    A. Rahman, and P. Vashishta, in The Physics of Superionic Conductors, edited by J. W. Perram (Plenum, New York, 1983 ), and J. P. Hansen, and I. R. McDonald, Theory of simple liquids (Academic Press, 1976).Google Scholar
  12. 12.
    D. Beeman and R. Alben, Adv. in Phys. 26:339 (1977).CrossRefGoogle Scholar
  13. 13.
    R. Fletcher, Practical Methods of Optimization (Wiley, New York, 1980), and F. H. Stillinger, and T. A. Weber, Science 225:983 (1984).CrossRefGoogle Scholar
  14. 14.
    G. M. Eliashberg, Zh. Eksp. Teo. Fiz. 38:966 (1960).Google Scholar

Copyright information

© Plenum Press, New York 1990

Authors and Affiliations

  • Marcos H. Degani
    • 1
    • 2
  • Rajiv K. Kalia
    • 1
  • P. Vashishta
    • 1
  1. 1.Materials Science DivisionArgonne National LaboratoryArgonneUSA
  2. 2.Instituto de Fisica e Química de São CarlosUSPSão CarlosBrasil

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