PERPENDICULAR MAGNETIC-ANISOTROPY OF THE EPITAXIAL FCC CO 60-ANGSTROM-NI/CU(001) SYSTEM/

We have studied the transition from perpendicular to in-plane magnetiz ation in a ferromagnetically coupled epitaxial Co/Ni/Cu(001) structure . Perpendicular magnetic anisotropy (PMA) up to 6 +/- 1.5 Angstrom Co thickness is observed. The value of the uniaxial Co volume anisotropy (K-V(Co)), which comes entirely from the shape anisotropy contribution , is explained by the absence of strain in the Co film, leading to a v anishing magnetoelastic anisotropy contribution to K(V)(Co)as evidence d by reflection high-energy electron diffraction results. We conclude that the critical thickness for PMA in this system can be controlled v ia strain in the Co film.