Numéro
J. Phys. IV France
Volume 02, Numéro C3, Décembre 1992
35 ème Colloque de Métallurgie de l'INSTN
MATERIAUX MAGNETIQUES
PROGRES ET PERSPECTIVES
Page(s) C3-223 - C3-227
DOI http://dx.doi.org/10.1051/jp4:1992333
35 ème Colloque de Métallurgie de l'INSTN
MATERIAUX MAGNETIQUES
PROGRES ET PERSPECTIVES

J. Phys. IV France 02 (1992) C3-223-C3-227

DOI: 10.1051/jp4:1992333

Propriétés dynamiques d'alliages ferromagnétiques cobalt/métal de transition, faiblement substitués en terres rares magnétiques

J. RUSSAT1, G. SURAN2, H. OUAHMANE2, M. RIVOIRE2 and J. SZTERN2

1  Commissariat à l'Energie Atomique, Centre d'Etudes de Bruyères-le-Châtel, BP. 12, 91680 Bruyères-le-Châtel, France
2  Laboratoire de Magnétisme et Matériaux Magnétiques, Centre National de la Recherche Scientifique, 1 place A. Briand, 92195 Meudon cedex, France


Abstract
Using radio-frequency (r-f) sputtering, we have prepared in presence of a static magnetic field, ferromagnetic thin films of composition (Co93Zr7)100 - yREy (RE = Nd, Pr, Dy, Tb... a magnetic rare earth element). The study was performed for small amounts of RE substitution (0 < y < 3). These films exhibit attractive soft magnetic properties similar to CoZr alloys : low coercivity (Hc ~ 1 Oe), and a high saturation induction (Bs 10 kG). A low in-plane uniaxial anisotropy Hk forms, whose magnitude depends upon the composition and the preparation parameters. Substitution by RE atoms affects essentially the µ frequency-response. Depending on the nature, the concentration of RE atoms and on the value of Hk, a high relative rotational permeability µ (µ' ~ 500-3000 at frequencies up to 500 MHz) was obtained. Also depending on RE and on y, high µ" (µ" ~ 400-3000 at ν ~ 1 GHz) distributed over a very broad frequency range (Ɗν ~ 500-2500 MHz) was measured. Using the Landau-Lifshitz equations for high frequency permeability and the values of the magnetic parameters measured by FMR, experimental spectra could be well approximated.



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