Magnetostriction of Thin Ni‐Films

Magnetostriction of thin Ni‐films is investigated by the multibeam interference method. The magnetostriction constant λs is calculated from the changes in the mica substrate's deflection as it yields to the stresses in the films. Its value does not differ appreciably from that of bulk nickel. The deflections of the mica substrate due to the stresses stemming from the evaporation process are apparent in the interference pattern as a system of hyperbolas. This can be explained as originating in a saddle‐like deflection of the substrate.