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Micromagnetic Spin Structure

  • R. Skomski
Chapter
Part of the Lecture Notes in Physics book series (LNP, volume 569)

Abstract

Magnetization inhomogenities, associated for example with grain boundaries, give rise to local spin-dependent potentials and affect the magnetoresistance. The local magnetization M(r) depends on both intrinsic and extrinsic factors. Intrinsic properties, such as spontaneous magnetization and anisotropy, are determined on an atomic scale and are basically independent of the material’s real structure and history. Extrinsic properties, such as remanence and coercivity, are linked to magnetic hysteresis, realized on mesoscopic or macroscopic length scales, and are strongly real-structure dependent. The local magnetization M(r), which determines the magnetoresistance, is determined from a nonlinear and nonlocal micromagnetic energy functional containing the intrinsic properties as parameters. This chapter focuses on basic micromagnetic effects and on the spin structure at grain boundaries. Continuum and layer-resolved analytic calculations yield a quasi-discontinuity of the magnetization between misaligned and in-completely exchange-coupled grains and a disproportionally large grain-boundary magnetoresistance.

Keywords

Domain Wall Magnetocrystalline Anisotropy Spontaneous Magnetization Local Magnetization Orbital Moment 
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.
    M. N. Baibich, J. M. Broto, A. Fert, F. Nguyen Van Dau, F. Petro., P. Etienne, G. Creuzet, A. Friederich, and J. Chazelas, Phys. Rev. Lett. 61, 2472 (1988).CrossRefGoogle Scholar
  2. 2.
    A. E. Berkowitz, J. R. Mitchell, M. J. Carey, A. P. Young, S. Zhang, F. E. Spada, F. T. Parker, A. Hutten, and G. Thomas, Phys. Rev. Lett. 68, 3745 (1992).CrossRefGoogle Scholar
  3. 3.
    J. Q. Xiao, J. S. Jiang, and C. L. Chien, Phys. Rev. Lett. 68, 3749 (1992).CrossRefGoogle Scholar
  4. 4.
    J. F. Gregg, W. Allen, K. Ounadjela, M. Viret, M. Hehn, S. M. Thompson, and J. M. D Coey, Phys. Rev. Lett. 77, 1580 (1996).CrossRefGoogle Scholar
  5. 5.
    P. M. Levy and S. Zhang, Phys. Rev. Lett. 79, 5110 (1997).CrossRefGoogle Scholar
  6. 6.
    R. von Helmolt, J. Wecker, B. Holzapfel, L. Schultz, and K. Samwer, Phys. Rev. Lett. 71, 2331 (1993).CrossRefGoogle Scholar
  7. 7.
    J. M. D. Coey, M. Viret, L. Ranno, and K. Ounadjela, Phys. Rev. Lett. 75, 3910 (1995).CrossRefGoogle Scholar
  8. 8.
    P. Schiffer, A. P. Ramirez, W. Bao, and S.-W, Cheong, Phys. Rev. Lett. 75, 3339 (1995).CrossRefGoogle Scholar
  9. 9.
    N. D. Mathur, G. Burnell, S. P. Isaac, T. J. Jackson, B.-S. Theo, J. L. MacManus Driscoll, L. F. Cohen, J. E. Evetts, and M. G. Blamire, Nature 387, 266 (1997).CrossRefGoogle Scholar
  10. 10.
    J. M. D. Coey, A. E. Berkowitz, Ll. Balcells, F. F. Putris, and A. Barry, Phys. Rev. Lett. 80, 3815 (1998).CrossRefGoogle Scholar
  11. 11.
    N. F. Mott and H. Jones, “The Theory of the Properties of Metals and Alloys”, (University Press, Oxford, 1936).Google Scholar
  12. 12.
    W. F. Brown, “Micromagnetics”, (Wiley, New York, 1963).Google Scholar
  13. 13.
    A. Aharoni, “Introduction to the Theory of Ferromagnetism”, (University Press, Oxford, 1996).Google Scholar
  14. 14.
    R. Skomski and J. M. D. Coey, “Permanent Magnetism”, (Institute of Physics, Bristol, 1999).Google Scholar
  15. 15.
    H. R. Hilzinger and H. Kronmüller, Phys. Lett. 51A 59 (1975).Google Scholar
  16. 16.
    M. Viret, D. Vignoles, D. Cole, J. M. D. Coey, W. Allen, D. S. Daniel, and J. F. Gregg, Phys. Rev. B 53, 8464 (1996).CrossRefGoogle Scholar
  17. 17.
    A. Gupta, G. Q. Gong, G. Xiao, P. R. Duncombe, P. Lecoeur, P. Trouilloud, Y. Y. Wang and V. P. Dravid, and J. Z. Sun, Phys. Rev. B 54, 15629 (1996).CrossRefGoogle Scholar
  18. 18.
    E. Ising, Z. Phys. 31, 253 (1925).CrossRefGoogle Scholar
  19. 19.
    W. Heisenberg, Z. Phys. 49, 619 (1928).CrossRefGoogle Scholar
  20. 20.
    F. Bloch, Z. Phys. 57, 545 (1929).CrossRefGoogle Scholar
  21. 21.
    H. Brooks, Phys. Rev. 58, 909 (1940).CrossRefGoogle Scholar
  22. 22.
    J. C. Slater, Rev. Mod. Phys. 25, 199 (1953).CrossRefGoogle Scholar
  23. 23.
    F. Bloch, Z. Phys. 74, 295 (1932).CrossRefGoogle Scholar
  24. 24.
    L. Landau and E. Lifshitz, Phys. Z. Sowjetunion 8, 153 (1935).Google Scholar
  25. 25.
    M. Kersten, Z. Phys. 44, 63 (1943).Google Scholar
  26. 26.
    F. Cyrot-Lackmann, J. Phys. Chem. Solids 29, 1235 (1968).CrossRefGoogle Scholar
  27. 29.
    R. Skomski, H.-P. Oepen, and J. Kirschner, Phys. Rev. B 58, 11138(1998).CrossRefGoogle Scholar
  28. 30.
    F. Bloch and G. Gentile, Z. Phys. 70, 395 (1931).CrossRefGoogle Scholar
  29. 31.
    E. C. Stoner and E. P. Wohlfarth, Phil. Trans. Roy. Soc. A240, 599 (1948).CrossRefGoogle Scholar
  30. 33.
    C. Kittel, Rev. Mod. Phys. 21, 541 (1949).CrossRefGoogle Scholar
  31. 34.
    D. J. Craik and R. S. Tebble, Rep. Prog. Phys. 24 116 (1961).CrossRefGoogle Scholar
  32. 35.
    S. Chikazumi, “Physics of Magnetism”, (Wiley, New York, 1964).Google Scholar
  33. 36.
    R. Becker and W. Döring, “Ferromagnetismus”, (Springer, Berlin, 1939).Google Scholar
  34. 38.
    R. Skomski, J. Appl. Phys. 83, 6503 (1998).CrossRefGoogle Scholar
  35. 39.
    R. Skomski, J. P. Liu, and D. J. Sellmyer, Phys. Rev. B 60, 7359 (1999).CrossRefGoogle Scholar
  36. 40.
    R. Skomski and D. J. Sellmyer, J. Appl. Phys. 87, 4756 (2000).CrossRefGoogle Scholar
  37. 41.
    E. Kneller, “Ferromagnetismus” (Springer, Berlin, 1962).Google Scholar
  38. 42.
    R. Skomski, J. P. Liu, J. M. Meldrim, and D. J. Sellmyer, in “Magnetic Anisotropy and Coercivity in Rare-Earth Transition Metal Alloys”, eds., L. Schultz and K.-H. Müller, (Werkstoffinformationsgesellschaft, Frankfurt/M., 1998), p. 277.Google Scholar
  39. 43.
    R. Harris, M. Plischke, and M. J. Zuckermann, Phys. Rev. Lett. 31, 160 (1973).CrossRefGoogle Scholar
  40. 44.
    K. Moorjani and J. M. D. Coey, “Magnetic Glasses”, (Elsevier, Amsterdam, 1984).Google Scholar
  41. 45.
    E. M. Chudnovsky, W. M. Saslow, and R. A. Serota, Phys. Rev. B 33, 251 (1986).CrossRefGoogle Scholar
  42. 46.
    R. Skomski, J. Magn. Magn. Mater. 157–158, 713 (1996).Google Scholar
  43. 47.
    T. Schre. and J. Fidler, J. Magn. Magn. Mater. 175–181, 970 (1998).Google Scholar
  44. 48.
    R. Skomski and J. M. D. Coey, Phys. Rev. B 48, 15812 (1993).CrossRefGoogle Scholar
  45. 51.
    D. J. Sellmyer, M. Yu, R. A. Thomas, Y. Liu, and R. D. Kirby, Phys. Low-Dim. Struct. 1–2, 153 (1997).Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2001

Authors and Affiliations

  • R. Skomski
    • 1
  1. 1.Department of Physics and Astronomy and Center for Materials Research and AnalysisUniversity of NebraskaLincolnUSA

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