Properties of a submicrometer x‐ray beam at the exit of a waveguide

This report discusses the properties of a 13‐keV submicrometer x‐ray beam exiting from a waveguide. Waveguides for this spectral regime can be constructed by enclosing a low‐absorbing material between highly absorbant metals. Best performance is found for about 0.1 μm guiding layer thickness. Measurements of the photon beam size close to the exit and of the intensity distribution far from the exit will be presented. From these data one derives a beam size at the exit which is identical to the guiding layer thickness. This number being in the submicrometer range offers interesting perspectives for microscopy experiments in the hard x‐ray range.