9423013 Moodera Experimental investigation of the properties of magnetic materials by the surface-sensitive technique of spin-polarized tunneling is the aim of this research program. In particular, electron tunneling between ferromagnetic metals, through ferromagnetic insulators, and exchange effects in ultrathin films, and at the interfaces between ferromagnetic metals and paramagnetic metals will be studied. Planar tunnel junctions will use superconductors as electron-spin detectors at low temperature and voltage. Our recent success in using ferromagnetic metals as electron-spin detectors at room temperature and higher voltages greatly broadens this field of research and suggests technological uses. %%% Improvement of computer magnetic memory systems is currently of high priority. Study of surfaces and interfaces has become increasingly pertinent from the point of present and future technology. This is a proposal for the study of the physics of magnetic effects in thin film surfaces and trilayers using the technique of spin-polarized tunneling. The recently discovered large magnetoresistance effects in ferro-magnetic tunnel junctions at room temperature promise important applications for these effects in READ/WRITE sensors and memory elements. ***
