Ultrafast resonant magnetic scattering at the European XFEL
by
FB42
Magnetic materials are of interest in a wide range of nanotechnologies such as for data storage, memory, logic, and sensing applications. Today, there is a strong desire to manipulate magnetism at timescales below the picosecond. There is therefore a high motivation in studying ultrafast magnetism
at the nanoscale. Resonant soft X-ray scattering and imaging are unique techniques that can combine
nanometer spatial resolution and femtosecond time resolution in the study of magnetic materials.
We performed X-ray scattering experiments at the X-ray free electron laser in Hamburg, the European
XFEL to measure the demagnetization in different magnetic thin films. This thesis will first present
the different ways X-rays are generated. I will in particular focus on synchrotron radiation and the
recent the development of X-ray free electron lasers (XFEL). I will then introduce resonant soft X-ray
measurements and show how resonant X-ray scattering and X-ray imaging are powerful tools to
investigate magnetism. I will illustrate this with two experiments carried out at the European XFEL in
Hamburg. In the first experiment we performed X-ray holography to image magnetic structures in
nanodots. In the second experiment we performed resonant X-ray scattering on magnetic thin films
with stripe domains to elucidate domain motions at the ultrafast timescales.
