Thermopower Near Magnetic and Order-Disorder Critical Points

  • R. D. Parks
  • R. Orbach

Abstract

The thermopower anomalies observed at ferromagnetic, antiferromagnetic, and order-disorder critical points are characterized by specific heat like singularities in the temperature derivatives of the thermopower S. The nature of the anomaly is prescribed by the temperature dependence of the zero time localized spin-spin (or concentration-concentration) correlation functions \( g\vec k\left( {t = 0} \right) \) for large momentum transfers (\( \left| {\vec k} \right|\sim 2{k_F} \)). Inelastic scattering is important as a consequence leading to an expression for the critical thermopower which contains convoluted functions of the frequency dependent localized spin-spin correlation functions \( g\overrightarrow k\left(\omega\right) \). The observed temperature dependence of S is thought to reside primarily in the behavior of the resistivity p near the critical temperature, the variation of the thermopower integrals with temperature being rather smooth in this regime. When the momentum transfer is small (e.g. ferromagnetic semiconductors) so that the localized spin system’s fluctuations critically slow down, elastic scattering will dominate the thermopower. In such a case, S is directly proportional to the localized spin-spin correlation function \( {g_{2{k_F}}}\left({\omega=0} \right) \).

Keywords

Fermi Surface Elastic Scattering Ising Model Temperature Derivative Time Correlation Function 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    S.H. Tang, R.P. Craig and T.A. Kitchens, Phys. Rev. Lett. 27, 593 (1971).CrossRefGoogle Scholar
  2. 2.
    Ora Entin-Wohlman, Guy Deutscher, and R. Orbach, Phys. Rev. B14, 4015 (1976).CrossRefGoogle Scholar
  3. 3.
    G.A. Thomas, K. Levin and R.D. Parks, Phys. Rev. Lett. 29, 1321 (1972).CrossRefGoogle Scholar
  4. 4.
    I. Zoric, G.A. Thomas and R.D. Parks, Phys. Rev. Lett. 30, 22 (1973).CrossRefGoogle Scholar
  5. 5.
    R.D. Parks, A.I.P. Conf. Proc. 5, 630 (1972).Google Scholar
  6. 6.
    B.I. Halperin and P.C. Hohenberg, Phys. Rev. 177, 952 (1969).CrossRefGoogle Scholar
  7. 7.
    D.J.W. Geldart, Phys. Rev. 815, 3455 (1977).Google Scholar
  8. 8.
    P.G. De Gennes and J. Friedel, J. Phys. Chem. Solids 4, 71 (1958).CrossRefGoogle Scholar
  9. 9.
    M.E. Fisher and R.J. Burford, Phys. Rev. 156, 583 (1967).CrossRefGoogle Scholar
  10. 10.
    M.E. Fisher and J.S. Langer, Phys. Rev. Lett. 20, 655 (1968).CrossRefGoogle Scholar
  11. 11.
    T.G. Richard and D.J.W. Geldart, Phys. Rev. B15, 1502 (1977).Google Scholar
  12. 12.
    S. Alexander, J.S. Heiman and I. Balberg, Phys. Rev. 813, 304 (1976).Google Scholar
  13. 13.
    T. Kasuya and A. Kondo, Solid State Comm. 14, 249 (1972).CrossRefGoogle Scholar
  14. 14.
    W.J. Nillis and S. Legvold, Phys. Rev. 180, 581 (1969).CrossRefGoogle Scholar
  15. 15.
    Sigurds Arajs, Norman L. Reeves and Elmer E. Anderson, J. Appl. Phys. 42, 1691 (1971).Google Scholar
  16. 16.
    D. Charkaborty and R.D. Parks, to be published.Google Scholar
  17. 17.
    L. Guttman and H.C. Schnyders, Phys. Rev. Letters 22, 520 (1969).CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 1978

Authors and Affiliations

  • R. D. Parks
    • 1
  • R. Orbach
    • 2
  1. 1.University of RochesterRochesterUSA
  2. 2.University of CaliforniaLos AngelesUSA

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