Journal of Low Temperature Physics

, Volume 60, Issue 3–4, pp 223–238 | Cite as

Specific heat and magnetization of superconducting niobium in the mixed state

  • N. J. Imfeld
  • W. Bestgen
  • L. Rinderer
Article

Abstract

The thermodynamics of the mixed state of niobium is reconsidered. Critical fieldsH c (t),Hc1(t),and Hc2(t), Maki parameters κ1 and κ2, magnetization, and specific heat are measured with a computer-controlled magnetometer and calorimeter. The results show quantitative discrepancies with the isotropic Gorkov-Brandt theory over almost the whole mixed state. Computations based on Fermi surface anisotropy using a scaling ofHc2 provide a much better agreement with the experimental magnetization curves already in the limit of “weak nonlocality,” thus suggesting a numerical evaluation of the anisotropic terms in the Gorkov-Brandt theory.

Keywords

Anisotropy Calorimeter Niobium Magnetic Material Fermi Surface 

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References

  1. 1.
    U. Kumpf,Phys. Stat. Sol. (b),44, 829 (1971).Google Scholar
  2. 2.
    U. Essmann,Physica 55, 83 (1971).Google Scholar
  3. 3.
    J. J. Wollanet al., Phys. Rev. B 10, 1874 (1974).Google Scholar
  4. 4.
    E. Seidl and H. W. Weber,J. Low Temp. Phys. 30, 273 (1978).Google Scholar
  5. 5.
    K. H. Berthel and B. Pietrass,J. Low Temp. Phys. 33, 127 (1978).Google Scholar
  6. 6.
    H. R. Kerchneret al., Phys. Rev. B 21, 86 (1980); D. K. Christenet al., Phys. Rev. B 21, 102 (1980).Google Scholar
  7. 7.
    H. R. Kerchneret al., Phys. Rev. B 24, 1200 (1981).Google Scholar
  8. 8.
    A. Abrikosov,Sov. Phys. JETP 5, 1174 (1957).Google Scholar
  9. 9.
    L. P. Gorkov,Sov. Phys. JETP 9, 1364 (1959).Google Scholar
  10. 10.
    J. Bardeen, L. N. Cooper, and J. R. Schrieffer,Phys. Rev. 108, 1175 (1957).Google Scholar
  11. 11.
    E. Helfland and N. R. Werthamer,Phys. Rev. 147, 288 (1966).Google Scholar
  12. 12.
    G. Eilenberger and V. Ambegaokar,Phys. Rev. 158, 332 (1967).Google Scholar
  13. 13.
    W. Pesch and L. Kramer,J. Low Temp. Phys. 15, 367 (1974).Google Scholar
  14. 14.
    E. H. Brandt,Phys. Stat. Sol. (b)51, 345 (1972).Google Scholar
  15. 15.
    E. H. Brandt,J. Low Temp. Phys. 24, 409, 427 (1976);Phys. Stat. Sol. (b)77, 105 (1976).Google Scholar
  16. 16.
    P. C. Hohenberg and N. R. Werthamer,Phys. Rev. 153, 493 (1967).Google Scholar
  17. 17.
    W. H. Butler,Phys. Rev. Lett. 44, 1516 (1980).Google Scholar
  18. 18.
    H. W. Pohl and H. Teichler,Phys. Stat. Sol. (b)75, 205 (1976).Google Scholar
  19. 19.
    E. A. Burgemeisteret al., Physica 90B, 131 (1977).Google Scholar
  20. 20.
    P. F. Sullivan,Phys. Rev. 173, 679 (1968).Google Scholar
  21. 21.
    R. Bachmannet al., Rev. Sci. Instrum. 43, 205 (1972).Google Scholar
  22. 22.
    J. F. Cochranet al., Rev. Sci. Instrum. 137, 499 (1966).Google Scholar
  23. 23.
    G. P. Van der Meyet al., Physica 95B, 369 (1978).Google Scholar
  24. 24.
    N. E. Alekseyevskyet al., Fiz. Metal. metalloved. 37, 63 (1974).Google Scholar
  25. 25.
    E. H. Brandt,Phys. Stat. Sol. (b)64, 467 (1974).Google Scholar
  26. 26.
    K. Maki,Physics 1, 21 (1964).Google Scholar
  27. 27.
    J. M. Daams and J. P. Carbotte,J. Low Temp. Phys. 40, 135 (1980);43, 3 (1980).Google Scholar
  28. 28.
    B. B. Goodman,Phys. Lett. 12, 6 (1964).Google Scholar
  29. 29.
    R. R. Hake,Phys. Rev. 166, 471 (1968).Google Scholar
  30. 30.
    C. Eck, CERN report ND 77-3/1 (1981).Google Scholar
  31. 31.
    B. Efron,SIAM Rev. 21, 460 (1979).Google Scholar

Copyright information

© Plenum Publishing Corporation 1985

Authors and Affiliations

  • N. J. Imfeld
    • 1
  • W. Bestgen
    • 1
  • L. Rinderer
    • 1
  1. 1.Institut de Physique Experimentale de l' Universite de LausanneLausanneSwitzerland

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