Controllable electrical conduction at complex oxide interfaces

Oxide interfaces have sparked considerable interest due to their fascinating physical properties and promising possibilities for next-generation nanoelectronics. Three intriguing oxide interfaces, hetero-, homo-, and tubular interfaces, will be discussed in detail in this review. First, the development and fundamental properties of classical heterointerfaces will be elaborated. Using LaAlO₃/SrTiO₃ as a case study, we present the most generic approach to control the two-dimensional electron conduction at the heterointerface. Secondly, several key issues based on interesting observations on ferroic homointerfaces will be addressed. Multiple controls of fascinating functionalities based on multiferroic BiFeO₃ domain walls will be presented as a model system. Finally, as the most challenging task, we review a new type of complex oxide interfaces, the tubular interface. Further insights of recently emerged tubular interfaces in BiFeO₃/CoFe₂O₄ system will be explored, which serve as one of the focal roles in developing new functional interfaces and potentially new type of nanostructures.