Reconstructions at complex oxide interfaces

Perovskite-type oxides, ABO3, are of high interest since they exhibit a wide variety of properties. Having comparable oxygen backbone structures, perovskite-type oxides can easily be stacked on top of each other with atomic precision. This may result in advanced materials with new or enhanced functionalities. Moreover, near the interface, interplay between the different materials occurs, which may lead to interesting functionalities confined at the interface. For the development of device applications, it is important to understand the origin of the functionalities near the interface of oxide heterostructures. In this thesis, the interface behavior of perovskite-type oxide heterostructures was studied for four different cases: DyScO3 surface, SrTiO3-amorphous oxide, LaAlO3-SrTiO3 and LaTiO3-LaFeO3. Electronic, structural and chemical reconstructions were taken into account. It has been shown that the behavior of perovskite-type oxide interfaces is very sensitive to small variations in composition and structure near the interface.