Statistical Models of Ferrimagnetism

Theoretical study of a ferrimagnetic system with triangular symmetry under a longitudinal magnetic field

“…The usual argument that the sublattices magnetizations m A and m B tend to zero as the temperature approaches a critical temperature allows us to consider only linear terms in each sublattice magnetization for Eqs. (22) and (23). Consequently, all terms of the order higher than linear in Eqs.…”

“…[22] is the exceptional case. Here, as a simple procedure to use these identities for the evaluation of m A and m B ; let us introduce the well-known decoupling approximation…”

“…Consequently, all terms of the order higher than linear in Eqs. (22) and (23) can be neglected. From this procedure, we can obtain the following matrix equation:…”

“…(22) and (23). Finally, in order to obtain the initial susceptibility w of the system, it is necessary to calculate ðqm a =qH 0 Þ H 0 ¼ 0 (a ¼A or B) by differentiating the Eqs.…”

“…(22)-(24) for selected values of D=J A ; J AB =J A and J B =J A : InFig. 5, a set of isothermal magnetization curves is plotted with J B =J A ¼ 0:3 and changing J AB =J A ¼ 0:05 and d ¼ 0; in the system with S A ¼ 1 2 and S B ¼ 1 for different temperatures.…”