This book (Practical Electron Microscopy and Database) is a reference for TEM and SEM students, operators, engineers, technicians, managers, and researchers.
The superlattices of two perovskites SrTiO3 and LaTiO3have many important properties of naturally occurring charge-ordered systems, i.e. mixed-valence configurations near half-filling. Their lattice constants (see SrTiO3 and LaTiO3) are relatively well matched, and the continuity of the TiO6 octahedral lattice across the superlattice minimizes the perturbation of the electronic states near the chemical potential [1-2].
In HAADF z-contrast imaging mode, the intensity of electron scattering by the atoms depends on the atomic number Z. For the superlattice structure consisting of LaTiO3 and SrTiO3 layers, the brightest features are columns of La ions, the second brightest features are columns of Sr ions, and the Ti ions are weakly visible in between the LaTiO3 and SrTiO3 layers as shown in Figure 3519. The oxygen ions are not visible due to the much lower atomic number. Note that the number of the LaTiO3 and SrTiO3 layers is determined by the deposition recipe.
Figure 3519. HAADF image of superlattice structures consisting of LaTiO3 and SrTiO3 layers. The imaging optical axis is the  zone axis of the crystals. Adapted from .
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