A magnetic skyrmion is a special spin configuration with particle-like properties that can be found in non-collinear thin-films and bulk chiral magnets. This work shows measurements of these special structures using two techniques.
In the first part Resonant Elastic X-ray Scattering (REXS) is used to obtain reciprocal space maps of the non-collinear phases (helical phase, conical phase and hexagonal skyrmion lattice phase) of the bulk chiral magnet Cu2OSeO3. This is then further extended with Ferromagnetic Resonance (FMR) measurements by means of a magnetic excitation of the system with an oscillating external magnetic field. It is found out that the scattered intensity changes when the system is resonantly driven out of equilibrium. This change can be detected which leads to the novel technique REXS-FMR. The method has benefits over conventional FMR measurements when applied to systems with complex magnetic environments or phase coexistence because the magnetic phase that produces the measured FMR signal can be selected.
In the second part, real space imaging of magnetic skyrmions and other chiral magnetic textures is presented by means of Lorentz Transmission Electron Microscopy (LTEM). Theoretical results are presented that link the magnetic structure of a Neel or Bloch skyrmion with the obtained electron phase in LTEM. The experimental part shows Fresnel and Differential Phase Contrast (DPC) LTEM measurements of Cu2OSeO3 as well as of the room-temperature skyrmion hosting multilayer materials Pt/Co/Tb and Pt/Co/W. The measurements e.g. include magnetic phase diagrams, skyrmion-skyrmion interaction determination or a closer study of the properties of the skyrmion nucleation process
