X-RAY-FLUORESCENCE HOLOGRAPHY AND MULTIPLE-ENERGY X-RAY HOLOGRAPHY - A CRITICAL COMPARISON OF ATOMIC IMAGES

We compare x-ray fluorescence holography (XFH) and multiple-energy x-r ay holography (MEXH), two techniques that have recently been used to o btain experimental three-dimensional atomic images. For single-energy holograms, these methods are equivalent by virtue of the optical recip rocity theorem. However, XFH can only record holographic information a t the characteristic fluorescence energies of the emitting species, wh ile MEXH can record holographic information at any energy above the fl uorescent edge of the emitter, thus enabling the suppression of real-t win overlaps and other aberrations and artifacts in atomic images.