Interfacial defects induced electronic property transformation at perovskite SrVO/SrTiO and LaCrO/SrTiO heterointerfaces.

Unravelling the atomic structure and chemical species of interfacial defects is critical to understanding the origin of interfacial properties in many heterojunctions. Here, by combining advanced transmission electron microscopy, spectroscopy and first-principles calculations, we demonstrate interfacial Ti diffusion in SrVO/SrTiO and LaCrO/SrTiO heterointerfaces and uncover that the interfacial defects induce a significant change in electronic properties by showing an electronic transformation from the insulating state to metallic state at SrVO/SrTiO heterointerfaces due to the hybridization of interfacial Ti d, O p and V d, and a metallic to insulating state transformation at LaCrO/SrTiO because of Ti-Cr mixing induced charge redistribution in the interfacial layer.