9424339 Flynn We explore and control the magnetic behavior of rare-earth nanostructures. These are synthesized from rare-earth metals as stacks of sheets, tailored in thickness and content by molecular beam epitaxy. Bulk rare earths exhibit a rich variety of unusal magnetic behavior, including unique helimagnetism and large magnetostriction. The proposed research includes studies of structure, magnetism, magnetic microstructure, and magnetotransport in these novel materials configurations. Use is made of neutron scattering, x-ray scattering with synchrotron radiation, SQUID magnetometry, and transport measurements on lithographically processed structures. Of special interest are: control of magnetic phase stability and thin film microstructure; chemical synthesis of new magnetic nanostructures; prediction of magnetic couplings near interfaces; and transformation dynamics including fluctuation and inelastic processes. %%% We focus on the synthesis and properties of magnetic nanostructures made from rare-earth metals by molecular beam surface layer deposition. This controlled process assembles thin films layer by layer on a crystalline substrate, from selected element metals, in the form of high quality single crystals, with a designed chemical sequence of successive layers. The focus on rare-earth metals is driven by technical and scientific interest in their magnetic behavior. Our abiliity to tailor selected structures allows us to explore the interactions among the atomic magnetic moments that cause a rich variety of magnetic structures. The surface layer deposition process has a controlling influence on magnetism through the clamping of the film to the substrate, and through the resulting strain and thin film geometry. The ability to control magnetic behavior of these materials is of interest in connection with applications to the storage, switching, and manipulation of information using thin film magnetic devices. ***
