Two dimensional spectrum imaging of SrTiO3 in the <110> projection using the VG Microscopes HB603U with Nion aberration corrector and Gatan Enfina operating at 300 kV. The left hand panel (red) shows the Z-contrast image with the atomic positions of Sr, Ti and O shown as red, green and blue circles. The center and right hand panels show the integrated signal from the simultaneously acquired Ti L and O K edges (40 eV integration windows were used with a large 260 eV background fitting window to reduce possible artifacts). A beam current of about 50 pA and an exposure time of 0.025 s per pixel were chosen to minimize damage. The convergence angle was about 25 mrad; the column length was adjusted and a custom-designed objective lens winding was used to allow the whole bright-field disk to be admitted to the spectrometer without the use of additional coupling modules. Images recorded by A. R. Lupini.
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A Z-contrast image (left) of wurtzite GaN in the <211> projection, with the structure shown inset, Ga atoms in yellow, N atoms as small grey spheres, with a line trace from the dashed area (below) showing resolution of the Ga dumbbells just 0.63 Å apart (red arrows), and the N atoms also just visible (black arrows). The Fourier transform (right) shows information transfer to 0.63 Å. Images are raw data from the ORNL FEI Titan 80-300, recorded by A. R. Lupini.
