Oscillatory Indirect Coupling Between Perpendicularly Magnetized Co Monolayers Through Cu(111)


Co-monolayers, prepared by MBE on Cu(111)-surfaces at room temperature and covered by Cu, are ferromagnetic with a Curie-temperature of about 430 K. They are magnetized perpendicularly because of a strong perpendicular magnetic surface anisotropy of the Cu/Co(111)-interface. They provide a remarkably good representation of the 2-dimensional Ising model. The indirect coupling between these perpendicularly magnetized ferromagnetic monolayers was investigated using samples of type Cu(lll)/lCo/DCuCu/lCo/Cu, containing Co/Cu/Co-trilayers composed of Co-monolayers and a spacer consisting of DCu atomic layers of Cu(111). Torsion oscillation magnetometry of these samples showed clearly a coupling between the monolayers with an oscillatory dependence on DCu. The amplitude of the oscillation is strongly reduced if the coupled Co-films consist of 5 ML instead of 1 ML. The present controversy on the presence or absence of antiferromagnetic and oscillatory indirect coupling in the Co/Cu(111)-system is discussed in the light of these experiments. The discussion shows that the oscillatory coupling is an intrinsic property of ideal (111)-structures, and can be understood by the RKKY-type theory of indirect coupling between ferromagnetic monolayers. The usual application of this theory to the coupling between thicker films is justified. However, in the fcc(111)-system there is apparently a specific barrier against complete coalescence, resulting in a tendency to retain holes and channels in the Cu-spacer. This tendency is stronger in flat single-crystal samples than in sputtered films with high densities of atomic steps. Apparently, this results in competing ferromagnetic hole coupling which may more or less completely obscure the intrinsic oscillatory coupling, preferentially in samples grown on extremely flat single crystal surfaces.

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  1. [1]

    C. Kittel in Solid State Physics, ed. F. Seitz, D. Turnbull and H. Ehrenreich, New York 1968, Vol 22, p.1

  2. [2]

    J.B. Boyce and C.P. Slichter, Phys. Rev. Β 13, 379 (1976)

    CAS  Article  Google Scholar 

  3. [3]

    L.R. Walker and R.E. Wernstedt, Phys. Rev. Β 22, 3816 (1980)

    CAS  Article  Google Scholar 

  4. [4]

    S.S.P. Parkin, N. More and K.P. Roche, Phys. Rev. Lett. 64, 2304 (1990)

    CAS  Article  Google Scholar 

  5. [5]

    J. Unguris, R.J. Celotta and D.T. Pierce, Phys. Rev. Lett. 67, 140 (1991)

    CAS  Article  Google Scholar 

  6. [6]

    A. FuR, S. Demokritov, P. Griinberg and W. Zinn, J. Magn. Magn. Mat. 103. L 221 (1992)

    Article  Google Scholar 

  7. [7]

    P. Bruno and C. Chappert, Phys. Rev. Lett. 67 1602 (1991)

    CAS  Article  Google Scholar 

  8. [8]

    J.Q. Xiao, J.S. Jiang and C.L. Chien, Phys. Rev. Lett. 68, 3749 (1992)

    CAS  Article  Google Scholar 

  9. [9]

    S.S.P. Parkin, R. Bhadra and K.P. Roche, Phys. Rev. Lett. 66, 2152 (1991)

    CAS  Article  Google Scholar 

  10. [10]

    D.H. Mosca, F. Petroff, A. Fert, P. A. Schroeder, W.P. Pratt Jr. and R. Laloee, J. Magn. Magn. Mat. 94, LI (1991)

    Article  Google Scholar 

  11. [11]

    A. Cebollada, J.L. Martinez, J.M. Gallego, J.J. de Miguel, R. Miranda, S. Ferrer, G. Fillion and J.P. Rebouillat, Phys. Rev. Β 39, 9726 (1989)

    CAS  Article  Google Scholar 

  12. [12]

    D. Pescia, D. Kerkmann, F. Schumann and W. Gudat, Z. Phys. Β 78, 475 (1990)

    CAS  Article  Google Scholar 

  13. [13]

    Μ.Τ. Johnson, S.T. Purcell, N.W.E McGee, R. Coehoorn, J. aan de Stegge and W. Hoving, Phys. Rev. Lett. 68, 2688 (1992)

    CAS  Article  Google Scholar 

  14. [14]

    W.R. Bennett, W. Schwarzacher and W.F. Egelhoff, Jr., Phys. Rev. Lett. 65, 3169 (1990)

    CAS  Article  Google Scholar 

  15. [15]

    W.F. Egelhoff Jr. and M.T. Kief, Phys. Rev. Β 45, 7795 (1992)

    CAS  Article  Google Scholar 

  16. [16]

    M.T. Johnson, R. Coehoorn, J.J. de Vries, N.W.E. MeGee, J. aan de Stegge and P.J.H. Bloemen, Phys. Rev. Lett. 69, 969 (1992)

    CAS  Article  Google Scholar 

  17. [17]

    J. Kohlhepp, S. Cordes, H.J. Elmers and U. Gradmann, J. Magn. Magn. Mat. 111. L 231 (1992)

    CAS  Article  Google Scholar 

  18. [18]

    J. Kohlhepp, H.J. Elmers, S. Cordes and U. Gradmann, Phys. Rev. Β 45, 12287 (1992)

    CAS  Article  Google Scholar 

  19. [19]

    U. Gradmann and J. Muller, Z. angew. Physik 30, 87 (1970)

    CAS  Google Scholar 

  20. [20]

    U. Gradmann and J. Muller, Czech. J. Physics B 21, 553 (1971)

    Google Scholar 

  21. [21]

    U. Gradmann and J. Muller, phys. stat. sol. 27, 313 (1968)

    CAS  Article  Google Scholar 

  22. [22]

    U. Gradmann, J. appl. Phys. 40, 1182 (1969)

    CAS  Article  Google Scholar 

  23. [23]

    U. Gradmann, Appl. Phys. 3, 161 (1974)

    CAS  Article  Google Scholar 

  24. [24]

    U. Gradmann, W. Kummerle and R. Tham, Appl Phys. 10, 219 (1976)

    Article  Google Scholar 

  25. [25]

    J. Kohlhepp, H.J. Elmers and U. Gradmann, J. Magn. Magn. Mat., in the press

  26. [26]

    U. Gradmann, Ann.Phys. (Leipzig) 17, 91 (1966)

    CAS  Article  Google Scholar 

  27. [27]

    D.W. Pashley, Advan. Phys. 14, 327 (1965)

    CAS  Article  Google Scholar 

  28. [28]

    J.W. Matthews, in Physics of Thin Films, ed. G. Hass and R. Thun, Vol 4, p 137 (1967)

    Google Scholar 

  29. [29]

    A. Brodde and H. Neddermeyer, Ultramicroscopy 42–44. 556 (1992)

    Article  Google Scholar 

  30. [30]

    D- Greig, M.J. Hall, C. Hammond, B.J. Hickey, H.P. Ho, M.A. Howson, M.J. Walker, N. Wiser and D.G. Wright, J. Magn. Magn. Mat. 110, L 239 (1992)

    CAS  Article  Google Scholar 

  31. [31]

    J.P. Renard, P. Beauvillain, C. Dupas, K. Le Dang, E. Vélu, C. Marlière and D. Renard, J. Magn. Magn. Mat. 115, L 147 (1992)

    CAS  Article  Google Scholar 

  32. [32]

    C. Dupas, E. Kolb, K. Le Dang, J.P. Renard, P. Veillet and E. Vélu, preprint 1993

    Google Scholar 

  33. [33]

    A. Schreyer, K. Bröhl, J.F. Ankner, T.h Zeidler, P. Bödeker, N. Metoki, C.F. Majkrzak and H. Zabel, preprint 1993

  34. [34]

    H. Pinkvos, private communication

  35. [35]

    H. Pinkvos, H. Poppa, E. Bauer and J. Hurst, Ultramicroscopy 47, 339, (1992)

    CAS  Article  Google Scholar 

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This work was supported by the Deutsche Forschungsgemeinschaft.

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Correspondence to Ulrich Gradmann.

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Gradmann, U., Elmers, HJ. & Kohlhepp, J. Oscillatory Indirect Coupling Between Perpendicularly Magnetized Co Monolayers Through Cu(111). MRS Online Proceedings Library 313, 107–117 (1993). https://doi.org/10.1557/PROC-313-107

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