Simultaneous visualization of oxygen vacancies and the accompanying cation shifts in a perovskite oxide by combining annular imaging techniques

The defect structures around oxygen vacancies in perovskite-type oxides play very important roles in determining material properties through the change of the electronic state. Therefore, from the viewpoint of developing condensed matter physics and technological applications, it is crucial to obtain direct images of these structures. We report the simultaneous visualization of oxygen vacancies and the cation shifts around them in perovskite-type manganite by scanning transmission electron microscopy. The defective structure of the material makes it amenable to using Fourier analysis to obtain important structural information like the oxygen vacancy locations and the shift of nearby cation columns. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4714920]