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Nonlocality in spherical-aberration-corrected high-angle annular dark-field (HAADF) scanning transmission electron microscope (STEM) images is theoretically and experimentally examined using the absorption potential describing thermal diffuse scattering (TDS). A detailed comparison between the simulated and the experimentally obtained high-quality HAADF STEM images of an Si(110) bulk structure and a PbTiO3(100)/SrTiO3(100) interfacial structure unambiguously demonstrates the need to use a nonlocal TDS absorption potential. The nonlocality in the TDS absorption potential cannot be ignored in a detailed analysis of spherical-aberration-corrected HAADF STEM images of materials consisting of several heavy elements, although it can be completely disregarded for those consisting of only light elements.

A many-beam dynamical theory for plan-view high-resolution transmission electron microscopy (HRTEM) images of multilayer systems without the limitation of a superlattice cell is proposed. The accuracy of our method is examined by comparing convergent-beam electron-diffraction calculations of Si(011) and HRTEM calculations of a system of epitaxial Al(100) on GaAs(100). Furthermore, this method is applied to CdSe clusters embedded in MgO, where it is revealed that the relative shift of their crystal-lattice planes produces moiré-like fringes.

An extended method is proposed for the precise simulation of high-angle annular dark-field (HAADF) scanning transmission electron-microscope (STEM) images for materials containing elements with large atomic numbers and for thick specimens. The approach combines a previously reported method utilizing two kinds of optical potential [Watanabe, Yamazaki, HashimotoShiojiri (2001). Phys. Rev. B, 64, 115432] with a representation of a crystal sliced into multiple layers. The validity of the method is demonstrated by simulated images for elements with the diamond structure (Si, Ge and alpha-Sn) and for the perovskite BaTiO3.

From the Dirac equation with a periodic scalar potential, an n-beam dynamical formula for the matrix representation of high-energy electron diffraction by a crystal is developed. By combining this with the layer-doubling method, the diffraction from an assembly of crystal slabs having different structures and thicknesses can be evaluated. Dynamical calculations of aluminium, copper and gold at several accelerating voltages have been carried out in a completely parallel manner by the present method and the Bethe method derived from the relativistic Schrodinger equation by replacing corrected mass and wavelength. The relativistic Schrodinger equation is found to be applicable for n-beam dynamical calculations for the Laue case.