Nanosession: 2D Electron Systems ‐ Atomic Configurations

This chapter discusses the first‐principles characterization of the structural and electronic properties of (SrTiO3)5/(SrRuO3)1 superlattices. The mechanism to create the two‐dimensional electron gas (2DEG) is totally new and based on the difference in electronegativity between Ru and Ti. Experimental evidence for intermixing and an insulating behaviour was reported for the DyScO3 /SrTiO3 interface. A number of novel phenomena including 2DEGs, charge ordering, electronic and atomic reconstructions and metal insulator transitions have been observed at complex oxide interfaces. The chapter presents how a controlled variation of the cation‐stoichiometry of STO thin films can be utilized to tailor the electronic properties of the LaAlO3 (LAO)/ SrTiO3 (STO)‐interface. The discovery of 2DEG at the interface of the two band insulators LAO and STO above a critical overlayer thickness of three monolayers (ML) of LAO has triggered intense investigations of oxide heterostructures. insulators; metal‐insulator transition; stoichiometry; two‐dimensional electron gas