Magnetodynamics of Nanostructured Metal Oxides

We aim at gaining a better fundamental understanding of electromagnetic properties of novel nano-scale ferromagnetic systems. In particular we are interested in the interaction of such materials with a spin-polarised current. Devices utilising these prope rties might become important as sensors and detectors in industrial applications. For optimum performance of such devices materials with high spin-polarisation as well as a high degree of interaction with electrical currents or fields are wanted. Good c andidates for this are metal oxides with a high degree of a spin polarisation. In the proposed project we will address the challenges of structuring and understanding the magnetodynamics of half-metal based nanostructures from both an experimental and the theoretical approach. Through thoroughly investigating the growth parameter space we will be able to fine tune growth and lithography parameters to be able to grow epitaxial films in layered heterostructures suitable for further probing and lithography . Lithography techniques will be adopted in order to explore the size, shape and composition effects. We will utilise scanning tunneling microscopy based techniques to form point contacts for resistive measurements. Through directly forming contacts to t he sample we can probe size and shape effects on a local scale. We will also explore how to combine this technique with radio frequency measurements, of either current excited spin waves, or to explore spin pumping through radio frequency exposure of the samples. Through theoretical investigations of model systems we will develop models for Gilbert damping and spin-transfer torques in ferromagnets. We will develop advanced transport theories to elucidate the dependence of the magnetization dynamics on ma terial parameters such as e.g. spin-orbit scattering, elastic scattering, and magnetization. This will us to understand and predict the dynamical interplay between spin polarized current and magnetization dynamics.