Dielectric properties of NaNbO3:SrTiO3 interface nanolayer

Abstract

NaNbO 3 : SrTiO 3 interface nanolayers are studied by combining first-principles modeling and experimental approach. The nature of NaNbO 3 : SrTiO 3 interface is investigated using density-functional theory calculations. Interface parameters are experimentally estimated using analysis of the dielectric response of SrTiO 3 and NaNbO 3 epitaxial films and NaNbO 3 : SrTiO 3 superlattices. It is shown that NaNbO 3 : SrTiO 3 interfaces can be approximated by dielectric nanolayers with thickness 1-2 nm and with temperature independent permittivity 25-55. Mechanism responsible for the nanolayer formation is the ionic charge mismatch between constituents.

Interface electronic structure in a metal/ferroelectric heterostructure under applied bias

“…Such measurements under applied bias are even more challenging. Several groups have conducted electrical measurement on these systems 9,11,12 but they do not directly probe the microscopic interfacial electronic structure. X-ray photoelectron spectroscopy (XPS) can reveal the electronic structure.…”