Advertisement

Journal of Low Temperature Physics

, Volume 105, Issue 5–6, pp 1237–1242 | Cite as

Upper critical field of Ba1−xK x BiO3 measured by magnetotunneling spectroscopy

  • P. Samuely
  • P. Szabó
  • A. G. M. Jansen
  • P. Wyder
  • J. Marcus
  • L. Baril
  • C. Escribe-Filippini
Josephson Effects and Tunneling
  • 17 Downloads

Abstract

In contrast to the conventional picture the upper critical fields measured by magnetoresistance in high-Tc superconductors including cubic Ba1−xKxBiO3, reveal a positive curvature in the temperature dependence. Several explanations have been proposed, but in magnetoresistance measurements flux-flow phenomena can play a role. We address the problem by tunneling spectroscopy, where we measure the superconducting density of states. The elastic tunneling current has been measured in the whole temperature and magnetic-field range up to the critical values. The obtained Hc2(T) dependence is in agreement with the Werthamer-Helfand-Hohenberg prediction.

PACS numbers

74.50 74.60e 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    D.J.C. Walker et al.,Phys. Rev. B 51, 9375 (1995).Google Scholar
  2. 2.
    M. Affronte et al.,Phys. Rev. B 49, 3502 (1994).Google Scholar
  3. 3.
    T. Klein et al.,Phys. Rev. B 53, 9337 (1996).Google Scholar
  4. 4.
    N.R. Werthamer, E. Helfand and P.C. Hohenberg,Phys. Rev. 147, 295 (1966).Google Scholar
  5. 5.
    S. Pei et al.,Phys. Rev. B 41, 4126 (1990).Google Scholar
  6. 6.
    Q. Huang et al.,Nature (London) 347, 369 (1990); P. Szabó, P. Samuely and M. Kupka, inProc. VII Intnl. Symposium on Weak Superconductivity, p.85, eds. S. Benacka, P. Seidel, V. Strbík, IEE SAS Bratislava 1994.Google Scholar
  7. 7.
    R.C. Dynes, V. Narayanamurti and J.P. Garno,Phys. Rev. Lett. 41, 1509 (1978).Google Scholar
  8. 8.
    E.Guyon, A. Martinet, J. Matricon and P. Pincus,Phys. Rev. 138, A746 (1965).Google Scholar
  9. 9.
    James L. Levine,Phys. Rev. 155, 373 (1967).Google Scholar
  10. 10.
    J. Millstein and M. Tinkham,Phys. Rev. 158, 325 (1967).Google Scholar
  11. 11.
    M. Tinkham,Introduction to Superconductivity, McGraw-Hill, Kogakusha, Tokyo, 1975.Google Scholar
  12. 12.
    H. Won and K. Maki,Phys. Rev. B 53, 5927 (1996).Google Scholar
  13. 13.
    M. Suzuki, K. Komorita and M. Nagano,J. Phys. Soc. Jap. 63, 1449 (1994).Google Scholar
  14. 14.
    S.-Y. Hsu, J.A. Chervenak and J.M.Vales, Jr.,Phys. Rev. Lett. 75, 132 (1995).Google Scholar

Copyright information

© Plenum Publishing Corporation 1996

Authors and Affiliations

  • P. Samuely
    • 1
  • P. Szabó
    • 1
  • A. G. M. Jansen
    • 1
    • 2
  • P. Wyder
    • 1
    • 2
  • J. Marcus
    • 1
    • 3
  • L. Baril
    • 1
    • 3
  • C. Escribe-Filippini
    • 1
    • 3
  1. 1.Institute of Experimental PhysicsSlovak Academy of SciencesKošiceSlovakia
  2. 2.Grenoble High Magnetic Field LaboratoryMPI-FKF and CNRSGrenoble Cedex 9France
  3. 3.Laboratoire d'Etudes des Propriétés Electroniques des SolidesCNRSGrenoble Cedex 9France

Personalised recommendations