Scientific Highlights

The spot size of a Fresnel Zone Plate lens is mainly determined by the zone widths of its outermost zone. It is therefore essential to fabricate zone plates with structures as small as possible for high-resolution X-ray microscopy. Researchers at the Laboratory for Micro- and Nanotechnology at the PSI have now developed Fresnel zone plates with zone widths well below 10 nm, down to 6.4 nm. These lenses are capable of pushing resolution in X-ray microscopy to the single-digit regime.

PSI scientists have developed tailored diffractive X-ray optics for a free electron laser that induces an optical vortex in extreme ultraviolet radiation. The experiment facilitates the first demonstration of orbital angular momentum in radiation created by a free electron laser in the extreme ultraviolet regime, with an extraordinary clean and defined wavefront. In a collaborative effort with researchers from the FERMI free electron laser in Trieste, Italy and from the University of Nova Gorica in Slovenia, the wavefront of the intense beams carrying an orbtial angular momentum was characterized. Furthermore, a method to characterize the footprint of a focused beam from a free electron laser was refined based on ablation imprints in polymers and subsequent treatment with organic solvents. In this way, the sensitivity of the imprint method could be enhanced to a dynamic range of three orders of magnitude in a single shot.

PSI scientists have developed a new type of X-ray optics that allows for analyzing the emission in resonant inelastic x-ray scattering (RIXS) experiments. The new approach combines the energy dispersion with imaging capabilities. In a collaborative effort with research groups from Göttingen and Hamburg, two new classes of RIXS experiments, energy mapping and RIXS imaging, have been demonstrated.

For the first time, researchers have produced a wafer-thin ferrimagnet, in which molecules with different magnetic centers arrange themselves on a gold surface to form a checkerboard pattern. Scientists at the Paul Scherrer Institute, in collaboration with their research partners, published the findings in the journal Nature Communications.

A new method of material modification using 172 nm UV photons enables to fabricate ultra-smooth and self-optimized polymer surfaces. The method, published in Advanced Materials Technologies, was used in the production of high quality micro-optics to remove typical process flaws after a 2-photon-lithography process.