Crystal Field Effects in Magnetic Superconductors

  • J. W. Lynn

Abstract

For the materials which have been found to simultaneously exhibit magnetic and superconducting properties, the magnetic ordering (of the rare earth ions) typically occurs below 1K, Since the associated magnetic energies are necessarily small we can anticipate that a proper understanding of the magnetic properties of these systems must include the effects of the crystalline electric field. In this paper we review the neutron scattering experiments carried out to date at the National Bureau of Standards research reactor on the Chevrel phase superconductors REMo6Se8, REMo6S8 (RE=rare earth) and on the substitutional alloy system (Ce1−cHoc)Ru2, with particular attention being given to the crystal field effects. The crystal field splittings in these systems are in fact generally found to be large in comparison with the characteristic magnetic energies and consequently the nature of the magnetic state at low temperatures and its influence on the superconducting properties is dictated primarily by the crystal field ground state.

Keywords

Entropy Anisotropy Graphite Sulfide Assure 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

References

  1. 1.
    O, Fischer, Appl. Phys.16, 1 (1978).ADSCrossRefGoogle Scholar
  2. 2.
    D. E. Moncton, J. Appl. Phys. 50, 1880 (1979).ADSCrossRefGoogle Scholar
  3. 3.
    G. Shirane, W. Thomlinson and D. E. Moncton (to be published).Google Scholar
  4. 4.
    S. Roth, Appl. Phys. 15, 1 (1978).ADSCrossRefGoogle Scholar
  5. 5.
    K. R. Lea, M. J. M. Leask and W. P. Wolf, J. Phys. Chem. Solids 23, 1381 (1962).ADSCrossRefGoogle Scholar
  6. 6.
    P. G. deGennes, in Magnetism, ed. Rado and Suhl (Academic Press, 1963) Vol. 3, pg. 115.Google Scholar
  7. 7.
    R. J. Birgeneau, J. Phys. Chem. Solids 33, 59 (1972).ADSCrossRefGoogle Scholar
  8. 8.
    W. Marshall and S. W. Loyesey, Theory of Thermal Neutron Scattering, (Oxford, 1971 ).Google Scholar
  9. 9.
    J. W. Lynn and R. N. Shelton, J. Appl. Phys. 50, 1984 (1979).ADSCrossRefGoogle Scholar
  10. 10.
    J. W. Lynn and R. N. Shelton, J. Mag. & Mag. Mat. (to be published).Google Scholar
  11. 11.
    H. Bethe, Ann. Phys. Opz. 3, 133 (1929).ADSCrossRefGoogle Scholar
  12. 12.
    R. W. McCallum, D. C. Johnston, R. N. Shelton, W. A. Fertig, and M. B. Maple, Sol. St. Comm. 24, 501 (1977).ADSCrossRefGoogle Scholar
  13. 13.
    J. W. Lynn, D. E. Moncton, G. Shirane, W. Thomlinson, J. Eckert, and R. N. Shelton, J. Appl. Phys. 49, 1389 (1978).ADSCrossRefGoogle Scholar
  14. 14.
    J. W. Lynn, D. E. Moncton, W. Thomlinson, G. Shirane, and R. N. Shelton, Sol. St. Comm. 26, 493 (1978).ADSCrossRefGoogle Scholar
  15. 15.
    M. Wilhelm and B. Hillenbrand, Z. Naturf 269, 141 (1972).See also B. T. Mattais, H. Suhl and E. Corenzwit, Phys. Rev. Lett. 1, 449 (1958).Google Scholar
  16. 16.
    J. W. Lynn, D. E. Moncton, L. Passell and W. Thomlinson, Phys. Rev. B21, 1 (1980).Google Scholar
  17. 17.
    J. W. Lynn and C. J. Glinka, J. Mag. & Mag. Mat. (to be published).Google Scholar
  18. 18.
    J. O. Willis, D. J. Erickson, C. E. Olsen and R. D. Taylor (to be published).Google Scholar

Copyright information

© Plenum Press, New York 1980

Authors and Affiliations

  • J. W. Lynn
    • 1
    • 2
  1. 1.Department of PhysicsUniversity of MarylandCollege ParkUSA
  2. 2.National Measurement LaboratoryNational Bureau of StandardsUSA

Personalised recommendations