Neutron scattering on magnetic thin films: Pushing the limits (invited)

Neutron scattering has been the scattering technique of choice for the anal ysis of magnetic structures and their dynamics for many decades. The advent of magnetic thin film systems has posed new challenges since such samples have inherently small scattering volumes. By way of examples, recent progre ss in the application of neutron scattering for the study of both magnetic structure and dynamics in magnetic thin film systems will be presented. Fir st, a combined high angle neutron scattering and polarized neutron reflecti vity investigation of the magnetic order of Cr and its influence on the exc hange coupling between the Fe layers in Fe/Cr superlattices is discussed. I t is shown that in the whole thickness range up to 3000 Angstrom, the magne tic structure is governed by frustration effects at the Fe/Cr interfaces. S econd, it is demonstrated that it is now possible to investigate the dynami c properties of magnetic thin films with neutron scattering. Unlike, e.g., Brillouin light scattering, inelastic neutron scattering provides access to large portions of the Brillouin zone. First results on spin wave excitatio ns in a Dy/Y superlattice are presented. (C) 2000 American Institute of Phy sics. [S0021-8979(00)92908-6].