Micron sized magnetic thin film structures have interesting magnetic properties. By adjusting size, shape, and material they can form a multitude of magnetic domain patterns. They consist of homogenously magnetized domains, which are separated by domain walls and magnetic vortices forming at the intersections of the domain walls.
We study the static and dynamic magnetic properties of such thin film structures. For this we use synchrotron based PhotoEmission Electron Microscopy (PEEM). By combining the naturally pulsed time structure of the synchrotron light with magnetic field pulses to the sample, we are able to study magnetization dynamics with a time resolution of tfwhm<100ps. This allows quantitative analysis of the excitations in such particles which can in turn be compared to simulations based on the Landau-Lifshitz-Gilbert equation.
We start by showing results on simple structures like squares exhibiting a Landau flux-closure pattern. Here all three subunits, the domains, the domain walls and the vortex can be identified and can be analyzed quantitatively.
By moving to more complex objects containing intentional defects or multiple vortices, we discuss switching between bi-stable vortex positions and vortex-antivortex interactions.
In the second part we will show the current capabilities for magnetic imaging of the recently installed Scanning Transmission X-ray Microscope (STXM) at the PolLux Beamline of the Swiss Light Source.
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