Aberration-corrected transmission electron microscopy -----From atomic structure to properties

Transmission electron microscopy (TEM) has proven to be a powerful tool for materials research. In particular, in the recent decade great progress in the technique of high-resolution transmission electron microscopy (HRTEM) has been made by the successful introduction of the spherical aberration (CS) correctors. Based on the CS -corrected electron microscope point resolution of sub-Ångstrom has been achieved. For crystalline materials aberration-corrected microscopy can be used for determining the position of atomic columns with a precision of a few picometers and for determining the chemical occupancy of atomic columns with the precision of a few atomic percent. With quantitative evaluation of image contrast of thin crystal the number of atoms within the atomic columns parallel to the viewing direction has been determined and it is possible to determine the 3D shape of nano-scale crystal with single atom precision. The successful application of the quantitative HRTEM to solving structural problems has played important role in understanding the relations between structure and properties of materials and is expected to make more progress in the future materials research. In the present lecture, we focus our discussion on TEM and HRTEM techniques and its applications to studying oxide materials.