Supersampled Scanning Transmission X-Ray Microscopy for High-Resolution Vibration-Independent Time-Resolved Imaging.

Scanning transmission x-ray microscopy (STXM) is a nanoscale imaging technique that can utilize several powerful contrast mechanisms for the quantitative mapping of chemical and physical materials properties. Spatial resolutions down to 7 nm at the soft x-ray energy range have been demonstrated. A limiting factor for high-resolution STXM imaging is given by the positioning precision of the sample with respect to the focusing optic, with the current state-of-the-art leading to significant overheads, especially at low pixel dwell times, and being vulnerable to unavoidable external vibration sources. In this work, we present a method called supersampled scanning microscopy that allows for a significant reduction of overhead times while simultaneously removing the effects of vibrational noise by sampling the position of the sample at a rate significantly higher than the vibration spectrum and reconstructing the sample transmission image from the recorded list of positions and detector counts. We demonstrate the performance of the technique with a set of proof-of-concept high-resolution imaging experiments.