Some magnetic properties of thin films in a mixed-spin surface Ising model

Magnetisation depth profiles in trilayer systems with mixed–spin interfaces—a contribution to temperature dependent GMR-potentials

“…Fig. 1 shows the position of two (1 0 0)-interfaces in s.c.-trilayer A(n)/A c B 1Àc /B(p)/A c B 1Àc /A(m) with exchange parameters: J AA ð JÞ; J AB and J BB : Three films of thickness, n; p and m (counted in a number of monatomic layers, respectively) are coupled via the mixed-spin single-(SLI) or double-layer interfaces (DLI) where the proximity effect is modelled assuming a disordered binary mixture A c B 1Àc of (A) spin-1 and (B) spin- 1 2 compounds with assumed concentration c. After thermodynamical ð/y T SÞ and configurational averaging ð/x A nj S c c v Þ using the integral operator technique [4,20,27,28] we obtain the system of 2ðn þ p þ m þ l I Þ nonlinear algebraic equations for the layered magnetisation…”

“…The summations run over all pairs of nearest neighbour sites while each of them is labelled with the number of plane (n) and in-plane vector (j), respectively. The method considered is based on Callen equations extended to take into account the stochastic spin-mixed magnetic structure introduced via stochastic operators x r nj [4,20,22,24]. We impose only the obvious restriction condition:…”

“…spin-mixed) both surface and interface problems in a single film and bilayer structures, respectively. It allowed us to describe the thermal reversal of magnetisation profiles in thin Fe-films in the case when the concentration of surface highspin component did not exceed the critical value that has been well defined according to the discussed T cr 2c phase diagram [20]. Further, we analysed also the variation of magnetisation depth profiles in heterostructure bilayer systems [4].…”

“…Thus, we present our analytical results of oneatom cluster approximation (1-ACA) based on the exact Callen equations extended for the case of stochastic spin-1 2 and spin-1 alloy structure in the form of trilayer systems [4,20,21]. The method is superior to the standard molecular field approach and thus it is particularly well suited for the description of mixed-spins as well as layered systems [22][23][24].…”

Role of Spin Mixing at Interface

“…Recently, we have presented our analytical results of one-atom cluster approximation (1-ACA) based on the exact Callen equations extended for the case of stochastic spin-1 and spin-1 alloy structure in the form of trilayer systems [20]. We analysed also the variation of MDP in heterostructure bilayer systems [21].…”