Magnetic Anisotropy of Helical and Collinear Magnets R2Fe17-XMnx
Magnetic anisotropy of the easy-plane type in the R2Fe17-хMnx systems with R = Ce and Lu weakens upon substitution of Mn for Fe. Temperature dependence of the first magnetic anisotropy constant (K1) of the R2Fe17-xMnx systems is described rather well in the single-ion model of magnetic anisotropy. However, in the case of the Ce2Fe17-хMnx helical ferromagnets the experimental variation of K1 is somewhat slower than that calculated by the third power of the spontaneous magnetization, in contrast to the Lu2Fe17-хMnx collinear ferromagnets, where K1 decreases slightly faster with increasing temperature as compared with this fit.
A. G. Kuchin "Magnetic Anisotropy of Helical and Collinear Magnets R2Fe17-XMnx", Solid State Phenomena, Vols. 168-169, pp. 192-195, 2011