MAGNETIZATION CURVES OF A SPIN-1 2 BILAYER SYSTEM (A2) (APB1-P)1 (B)2WITH DISORDERED INTERFACES/

A calculation is presented for the component magnetizations of an infi nite multilayer Ising system, consisting periodically of two layers of spin-1/2 A ions, two layers of spin-1/2 B ions, and a disordered laye r interface in between that is characterized by a random arrangement o f A and B ions like a two-dimensional A(p)B1-p alloy. The system is a simple cubic Ising-type structure with a coordination number z = 6. Th e model is general for ferro- and for antiferromagnetic A-B exchange c ouplings. The A-A and B-B exchange couplings are regarded as ferromagn etic. An effective field theory that goes beyond mean field, is employ ed to calculate the bulk-like transition temperature, the different co mponent magnetizations as well as the total bulk-like magnetization. T he component magnetizations are calculated for different realistic mod el values of ferro- and antiferromagnetic A-B exchange constants, as a function of temperature and of the concentration parameter p that cha racterizes the disorder in the interface. We show that the presence of a disordered interface may significantly affect the component and tot al magnetizations. In particular, for the case of antiferromagnetic ex change couplings, it is shown that the system can acquire a compensati on temperature for certain domains of values of the concentration para meter p in the disordered interface.