A method for applying a large persistent in-plane biaxial stress to influence the perpendicular magnetic anisotropy of magnetic thin films

摘要

We describe a method of applying large persistent biaxial in-plane tensile stress to thin films by loading a Ta substrate with hydrogen. Using this technique, we studied the influence of biaxial stress on the effective perpendicular magnetic anisotropy (K_(eff)) of Ni and Co_(50)Fe_(50) thin films. The K_(eff) of Ni increases by 40% whereas for Co_(50)Fe_(50) it decreases by 15% with respect to that of zero stress state upon applying biaxial stresses of 1.24 and 1.79 GPa, respectively. The results are analyzed using a simple model including shape and magnetoelastic anisotropy contributions. The influence of the saturation magnetization and the mechanical properties of the thin films on the maximum achievable relative change of K_(eff) is discussed.