KSEF R&D Excellence: Stability, Dynamics and Switching of Magnetic Nanostructures

Understanding magnetic materials of nanometer dimension and their interfaces is essential for the implementation of novel device architectures proposed for next-generation computers and other technologies. We propose to take advantage of the largely unexploited, but exquisite sensitivity of soft x-ray imaging and scattering techniques in the first systematic study of the spatial and temporal variations of nanostructure magnetization at the Advanced Light Source at Lawrence Berkeley National Laboratory. Principal objectives are: 1) To correlate soft x-ray microscopy and scattering data on nanoscale magnetic thin film structures with ferromagnetic resonance spectra and technologically relevant properties such as magnetoresistance, magnetization and magnetic switching behavior. 2) To develop several novel dynamic x-ray methods that will advance the state of the art in materials characterization, synthesis and design in academic and industrial arenas. 3) To identify unusual physical properties relevant to general classes of device architectures such as magnetoresistive hard drives, high capacity computer memory, and provide a better fundamental understanding of how to control ofnanoscale interface/surface processes. 4) To enhance materials synthesis capabilities, and support a coordinated program of graduate research and interdisciplinary training in cutting-edge nanoscience and technology at the University of Kentucky. Initial baseline x-ray studies of films, submicron dot and antidot lattices will be followed up by similar studies of true nanoscale systems, including "dumbbell" structures consisting of two magnetic features coupledQY a thin nanoscale bridge or interface (fabricated by Co-PI Prof. Hinds), and self-organized lattices of magnetic nanodots electrochemically deposited in AI or Ti films (fabricated by Prof. V. Singh's Group in UK Dept. Electrical Engineering). Additional activities in theory and numerical simulations, neutron reflectometry and thin film heat capacity will be undertaken via existing or planned collaborations that will not be directly supported by the requested KSEF funding.