CRYSTAL STRUCTURE, ELECTRONIC AND OPTICAL PROPERTIES OF EPITAXIAL ALKALINE EARTH NIOBATE THIN FILMS

Abstract

The interplay between the charge, lattice, spin and orbital freedom degrees in transition metal oxides (TMOs) lead to various unique physical and electronic properties. Perovskite oxides are one family of transition metal oxides that has received a disproportionate amount of attentions because of their unique structural compatibility and the large diversity of electronic phases. Alkaline earth niobates, such as CaNbO₃, SrNbO₃ and BaNbO₃, are typically 4d TMOs of which the physical properties are less understood and it is widely accepted that the 4d TMOs would the stronger hybridization with oxygen and a weaker on-site Coulomb interaction than that of TMOs with equivalent electronic configuration. Therefore, it would be very interesting to study the crystal structure, electronic and optical properties of alkaline earth niobates (MNbO₃ (M=Ca, Sr, Ba)) thin films.