Magnetization process of Ni/Si/Ni/GaAs multilayer and its magnetoresistance

Magnetization process and magnetoresistance measurement demonstrate existence of antiparallel spin state in a Ni/Si/Ni/GaAs multilayer. This occurred because of five times larger coercivity of Ni/GaAs than that of the Ni/Si. The hysteresis loop of Ni/Si/Ni/GaAs multilayer is found to be quite equal to the algebraic sum of that of the Ni/GaAs and Ni/Si bilayers, where the total Ni contents of the two bilayers are equal to that of the multilayer. The bottom Ni layer of the multilayer is mostly influenced by the underneath GaAs but not by the Si