Atom images and diffraction patterns of high Tc superconductors photographed by Ca-L2,3 shell loss electrons

Using Ca L2,3 (350 eV, 346 eV) shell loss electrons, images and diffraction patterns of high Tc superconductors containing single, double and triple Ca atomic columns were recorded with 6eV energy window using 200 kV field emission electrons and drift free goniometer. The images which were recorded with 60 seconds exposures had heavy quantum noise. Using image processing in real space and Fourier space, images of Ca-atoms were revealed. Characteristics of the nature of electron diffraction patterns are discussed.