GIANT MAGNETORESISTANCE IN GRANULAR ALLOYS - 2-BAND MODEL

Numerical simulation in the recursive Green's function method is exten ded to a two-band tight-binding model where itinerant s- and localized d-electrons coexist. This method enables us to make more realistic ca lculations of the giant magnetoresistance in magnetic multilayers and granular alloys containing noble metals, such as Co/Cu and Co/Ag. By u sing the present method, dependence of the magnetoresistance on the si ze of the magnetic clusters in granular alloys is examined and compare d with the experimental one as well as with that calculated before in the single-band model.