A method of improving spatial resolution in X-ray fluorescence holography

X-ray fluorescence holography (XFH) is a promising method for determination three-dimensional (3D) structure of local atoms. In this paper, we propose a method to improve the resolution of reconstructed atomic images in x-ray fluorescence holography. A Fe single crystal of body-centred lattice was used as a model for calculation of a hologram. Angular range dependence on spatial resolution of atomic images is discussed. The spatial resolution of the reconstructed image is proportional to the size of the hologram. A hologram recorded in the full 4pi sphere can provide complete holographic information. On the other hand, an atomic image obtained from a single energy XFH appears many aberrations and artifacts. By summing images reconstructed from the holograms recorded at several different energies, the atomic image became clearer. Furthermore, the spatial resolution of the atomic image increases with increase in the incident energy. And, the wider the range of incident energy is, the fewer aberrations and artifacts are. So, if an X-ray fluorescence hologram are recorded with the high incident energy and wide multiple-energy range in a 4pi solid angle, the atomic images can be reconstructed from the hologram with a high spatial resolution.