Holographic methods for X-ray and electron crystallography

摘要

FOllowing the invention of the laser, most application of holography have probably been in optics. Nevertheless, the historical record shows that the main inspiration for the invention of holography was Gabor's desire to image the atomic architecture of matter. In this paper we will focus on several modern applications of the holographic principle to X-ray and electron crystallography. Amongst X-ray applications, we will discuss the subject of surface X-ray diffraction, where diffracted amplitudes from the bulk of a sample act as a reference wave, and enable the reconstruction of surface electron density, and also the topic of protein crystallography, where knowledge of part of the structure enables the reconstruction of the unknown part by means of a mximum entropy algorithm. We will review recent results from photoelectron holography, and holographic low energy electron diffraction (LEED).