Role of the electronegativity for the interface properties of non-polar heterostructures
KAUST, Physical Science & Engineering Division - Thuwal 23955-6900, Kingdom of Saudi Arabia
Accepted: 26 March 2012
Density functional theory is used to investigate the interfaces in the non-polar ATiO3/SrTiO3 (A=Pb, Ca, Ba) heterostructures. All TiO2-terminated interfaces show an insulating behavior. By reduction of the O content in the AO, SrO, and TiO2 layers, metallic interface states develop, due to the occupation of the Ti 3d orbitals. For PbTiO3/SrTiO3, the Pb 6p states cross the Fermi energy. O vacancy formation energies depend strictly on the electronegativity and the effective volume of the A ion, while the main characteristics of the interface electronic states are maintained.
PACS: 73.20.-r – Electron states at surfaces and interfaces
© EPLA, 2012