Structural and Electronic Properties of BaO/MgO(001)-type Interface Studied via Aberration-corrected Transmission Electron Microscopy and First-principles Calculations

The properties of BaO/MgO-type interface in the BaZrO3/MgO(001) heterostructure are studied by aberrationcorrected high-resolution transmission electron microscopy combined with first-principles calculations.Experimental evidence demonstrates that cation displacement and vacancies occur at the interface. Our firstprinciple calculations show that cation displacement results from the electrostatic potential effect at the interface,and cation vacancies could lower the interfacial work of separation and enhance the interfacial stability of BaO/MgO-type interface. The results highlight that the effect of interfacial defects should be taken into account in understanding the film growth kinetics and properties in oxide heteroepitaxy.