STRONG ANTIFERROMAGNETIC COUPLING IN TAU-MNAL CO PERPENDICULAR MAGNETIC SUPERLATTICES ON GAAS/

This paper reports on the-structural and magnetic properties of tau Mn Al/Co superlattices epitaxially grown on AlAs/GaAs by Molecular Beam E pitaxy. In tau MnAl/Co superlattices with Co layer thickness < 8 Angst rom, a strong anti-ferromagnetic coupling between the ferromagnetic ta u MnAl and Co layers is found, as well as the presence of a large perp endicular magnetic anisotropy in both constituent layers, resulting in an unusually abrupt spin reversal at high fields. When increasing the Co layer thickness, the shape anisotropy in the Co layers dominates t his AF coupling and the constituent layers display different magnetiza tion directions: perpendicular (tau MnAl) and parallel (Co) to the gro wth plane.