The role of strain in magnetic anisotropy of manganite thin films

Abstract

We show the importance of the role of strain in La0.7Sr0.3MnO3 films by revealing the dominance of stress anisotropy effects over magnetocrystalline anisotropy effects in the magnetic anisotropy of these films. Magnetic anisotropy measurements of (001) and (110) La0.7Sr0.3MnO3 thin films on SrTiO3 and LaGaO3 substrates, with excellent structural quality, reveal twofold symmetry on (110) La0.7Sr0.3MnO3 films and fourfold symmetry on (001) films. Such symmetries can only be explained by stress anisotropy contributions in the plane of the film. In conjunction with the thickness dependence of the magnetic properties, the results indicate the dominant role of strain in the magnetic properties of these doped manganites.