Abstract
The electronic structure of oxygen vacancies in bulk perovskite oxides SrTiO and LaAlO is studied using the Heyd, Scuseria, Ernzerhof (HSE) hybrid density functional. In SrTiO the oxygen vacancy defect introduces a localized state comprised of and orbitals of the adjacent Ti atoms. This results in a bound state 0.7 eV below the conduction band edge. For LaAlO, the oxygen vacancy creates a deep state 2.19 eV below the conduction band edge. The defect state is a hybrid of the adjacent La 5 and the Al 3 states. We compute the formation energies of the neutral oxygen vacancy defect V in bulk SrTiO and LaAlO to be 6.0 and 8.3 eV, respectively.
4 More- Received 23 November 2011
DOI:https://doi.org/10.1103/PhysRevB.86.155105
©2012 American Physical Society