Magnetic superlattices: molecular beam epitaxial growth and properties of artificially and naturally-layered structures

Abstract

In this review we discuss examples of MBE (molecular beam epitaxial) growth of a variety of magnetic superlattices. We take this term as inclusive of both artificially-layered, periodic structures (i.e. magnetic multilayers) and natural superlattices (chemically-ordered intermetallic alloys with atomic layering along one or more crystallographic directions). Both types of structures exhibit a variety of novel phenomena which may be exploited in future information storage technologies. MBE growth enables mechanisms of these phenomena to be probed by providing structures with selected growth orientation. Also, it allows in situ characterization of surface and film structure, interface chemistry 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 permally / Au(111) and permalloy / Ag(111) multilayers exhibiting low-field giant magnetoresistance, the discovery of a new natural superlattice: hcp Co3Pt, the demonstration of high-performance magneto-optical recording in partially-ordered CoPt3 media and enhanced magneto-optical Kerr rotation and perpendicular magnetic anisotropy in spontaneously-ordered Fe-Pt alloy films. © 1995, All rights reserved.