Maskless off-axis X-ray Holography

Abstract: Off-axis X-ray holography is a lensless imaging technique that allows unambiguous retrieval of an object's exit-wave function with high fidelity. It has been used with great success to study nanoscale phenomena and spatio-temporal dynamics in solids, with sensitivity to the phase component of electronic and magnetic textures. However, the method requires patterning a nanostructured holography mask directly onto the sample. This invasive fabrication process is labor-intensive and defines a fixed field of view, limiting the range of applicable samples and diminishing the signal-to-noise ratio at high-resolution. In this work, we propose using wavefront-shaping X-ray diffractive optics to create a spatially structured probe with full control of its phase at the sample plane, obviating the need for a holography mask. We demonstrate in silico that the method can image nanoscale structures and magnetic textures. The proposed holography route can image extended regions of interest, enabling the investigation of a broad range of physical phenomena at the nanoscale including magnetism and electronic phase coexistence in quantum materials. We further envisage applications in phase-contrast imaging of other weakly absorbing objects in the realm of soft and biological matter research.