The effect of chemical disorder on the magnetic anisotropy of strained Fe-Co films

Strained Fe-Co films have recently been demonstrated to exhibit a large magnetocrystalline anisotropy (MCA) and thus to be of potential interest as magnetic storage material. Here, we show by means of density-functional (DF) calculations, that chemical order can remarkably enhance the MCA. We also investigate the effect of relaxation perpendicular to the applied strain and evaluate the strain energy as a function of Co concentration and substrate lattice parameter. On this basis, favourable preparation routes for films with a large perpendicular anisotropy are suggested. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim