High magnetostriction in low applied magnetic fields in amorphous Tb-Fe (hard)/Fe-B (soft) multilayers

High magnetostrictive amorphous multilayers consisting of Tb-Fe (hard) and Fe-B (soft) bilayers have been grown by dc sputtering. The layers have been found to be magnetically coupled for layer thicknesses between 25 and 75 /spl Aring/. As an effect of the coupling, high magnetostriction values (around 5/spl times/10/sup -4/) are obtained with low coercive fields (around 100 Oe). A qualitative magnetic model has been developed to account for the influence of the size and magnetic parameters on the multilayer magnetostriction and its saturation field, and the observed magnetization processes.