Dynamical processes in nanostructured and low-dimensional magnetic materials

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The current research into fundamental processes in magnetic materials that have one or more dimensions in the nanometer or submicron ranges is being driven by their immense potential for technological applications in the areas (for example) of new types of magnetic memory, ultrafast switching, and high-frequency devices. This is coupled with recent advances in growth and fabrication techniques that allow a wide variety of nanostructures composed of magnetic elements and their arrays to be reliably produced. Consequently, on the theoretical side there is a pressing need to understand at a fundamental level the dynamical processes taking place within such materials on these small length scales in order to engineer and enhance the properties of the devices and applications, as well as to predict new effects. This provides the primary objective and focus for this proposed program of theoretical research. The calculations will be carried out by using different quantum-mechanical techniques, often in conjunction with numerical simulation methods, and applied to the collective excitations or waves in the materials, e.g., the spin waves (or magnons), sometimes together with the vibrational waves (or phonons) and electronic excitations. Novel effects are expected to arise due to the spatial quantization of these waves confined in the finite materials and due to the presence of multiple surfaces and interfaces. It is known that nanostructured materials may sometimes display novel characteristics that are absent in their bulk constituent materials, as in the phenomenon of giant magnetoresistance for example, and can be utilized as the basis for new technologies. This provides another motivation for this field of research.