Influence of film structure on the perpendicular magnetic anisotropy in Fe/Tb multilayers

Fe/Tb multilayers are known to show perpendicular magnetic anisotropy (PMA), which is attractive for potential application in magneto-optical data storage. In this work. different kinds of magnetic properties are observed in two series of Fe/Tb multilayers with nominal terbium thicknesses of 0.5 and 1.0 nm, respectively. Although Tb thicknesses are the same, the [Tb(0.5 nm)/Fe(0.5nm)](50) film shows strong PMA, while the [Tb(1.0 nm)/Fe(0.5 nm)](30) film has superparamagnetic performance with weak PMA. The film structure is found to have an influence on the magnetic properties of the film, i.e., the Fe-Tb coupling that is the origin of PMA is affected by the antiferromagnetic Fe-Fe coupling when a Tb network forms in the [Tb(1.0 nm)/Fe(0.5 nm)](30) film. (C) 2002 Elsevier Science B.V. All rights reserved.