MAGNETIC SUPERLATTICES - MOLECULAR-BEAM EPITAXIAL-GROWTH AND PROPERTIES OF ARTIFICIALLY AND NATURALLY-LAYERED STRUCTURES

In this review we discuss examples of MBE (molecular beam epitaxial) g rowth of a variety of magnetic superlattices. We take this term as inc lusive of both artificially-layered, periodic structures (i.e, magneti c multilayers) and natural superlattices (chemically-ordered intermeta llic alloys with atomic layering along one or more crystallographic di rections). Both types of structures exhibit a variety of navel phenome na which may be exploited in future information storage technologies. MBE growth enables mechanisms of these phenomena to be probed by provi ding structures with selected growth orientation. Also, it allows in s itu characterization of surface and film structure, interface chemistr y and film growth modes. Furthermore. kinetic limitations in ordering of natural superlattices can be often be avoided by MBE growth. Recent key developments are reviewed including MBE growth of permalloy/Au(11 1) and permalloy/Ag(111) multilayers exhibiting low-field giant magnet oresistance, the discovery of a new natural superlattice: hcp Co3Pt, t he demonstration of high-performance magneto-optical recording in part ially-ordered CoPt3 media and enhanced magneto-optical Kerr rotation a nd perpendicular magnetic anisotropy in spontaneously-ordered Fe-Pt al loy films.