Title :
Determination of crystal-field parameters of Sm2Fe17N3 and Sm2Fe17 C3
Author :
Wirth, S. ; Wolf, M. ; Muller, K.-H. ; Skomski, R. ; Brennan, S. ; Coey, J.M.D.
Author_Institution :
Inst. fur Festkorper- und Werkstofforschung, Tech. Univ. Dresden, Germany
fDate :
9/1/1996 12:00:00 AM
Abstract :
The crystal-field parameters A20 and A40 were determined from the magnetocrystalline anisotropy constants K1 and K2 in a linear approximation for Sm2Fe 17Zx (Z=N,C) compounds. For the materials investigated, the values of K1 and K2 in a temperature range from 4.2-533 K have been obtained by a fit of demagnetization curves. The parameters An0 are calculated in two ways: (i) from the Ki at zero temperature and (ii) from the temperature dependence of the Ki. Both methods give equivalent results. The value A20≈-400 Ka0-2 has been obtained which corresponds to an inverse THOMAS-FERMI screening length q≈2.3 Å-1 calculated within the framework of the screened charge model
Keywords :
crystal field interactions; demagnetisation; exchange interactions (electron); ferromagnetic materials; iron alloys; magnetic anisotropy; permanent magnets; samarium alloys; 4.2 to 533 K; Sm2Fe17C3; Sm2Fe17N3; crystal-field parameters; demagnetization curves; inverse Thomas-Fermi screening length; linear approximation; magnetocrystalline anisotropy constants; screened charge model; Anisotropic magnetoresistance; Atomic measurements; Electrons; Elementary particle exchange interactions; Iron; Magnetic anisotropy; Perpendicular magnetic anisotropy; Polarization; Samarium; Temperature dependence;
Journal_Title :
Magnetics, IEEE Transactions on
