Hard magnetic functions

EuIn2P2 magnetic susceptibility shows a clear magnetic transition at about 24 K. In Fig. 11.5 c, magnetic susceptibility as a function of the a, a-h, and c direction were obtained on a plate crystal. The a axis exhibits the largest susceptibility and is the easy magnetization direction. The c axis is the hard magnetization direction. 

Fig. 35. Comparision of the hard magnetic properties of two hard magnetic materials a and b. (Left) Flux density B (full lines) and magnetic polarization J (dashed lines) as a function of the demagnetizing field strength H. (Right) Product BH (horizontal axis) plotted versus B (vertical axis) for both materials a and b. The working point corresponding to (BFf)max is indicated on the B(H) curve (left point for material a and b) by a filled and open circle, respectively.

Fig. 4.22. The ratio of ordering temperatures with and without an applied field Tn(B)/7n(0) as a function of the applied field B for KjFeFj. The points A are for B applied along the easy magnetic axis and the points O and are for B applied along hard magnetic axes. (Boersma et al., 1982.)...

In conclusion one must point out that the synthesis of Nd2Fei4B pure hard magnet films has not been achieved. The formation of various phases, often labeled with chemical formulae which are not known to exist, is observed as a function of the thermal treatments,... 

Higher-order spin terms are then added when the spacing of the fine structure is found to be a function of the magnetic field. In what follows we shall characterize each material by the value for D and E, and indicate by D that higher order terms were required. The analysis of spectra for the quantitative values of small terms is difficult, particularly when some expected lines have not been observed, and the associated errors hard to determine, so it is best to consult the original papers for terms beyond D and E. 

The magnetic field is independent of the choice of the gauge origin. So too are the computed magnetic properties if the wave function used is exact. Regrettably, we are not often afforded the opportunity to work with exact wave functions. For HF wave functions, one can also achieve independence of the gauge by using an infinite basis set, but that is hardly a practical option either. 

Fig. 26. Computed minimum value of the magnetic field Hm necessary to align the saturation value of magnetization along the hard axis as a function of biaxial strain component for two values of the hole concentrations in Gao.95Mno.05As. The symbol (100) - 1001) means that the easy axis is along IOO], so that Hun is applied along [001] (Dietl et al. 2001c).

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