0000000000154590
AUTHOR
Alexandre Sorokine
Electronic charge redistribution in LaAlO$_3$(001) thin films deposited at SrTiO$_3$(001) substrate: First principles analysis and the role of stoichiometry
We present a comprehensive first-principles study of the electronic charge redistribution in atomically sharp LaAlO$_3$/SrTiO$_3$(001) heterointerfaces of both n- and p-types allowing for non-stoichiometric composition. Using two different computational methods within the framework of the density functional theory (linear combination of atomic orbitals and plane waves) we demonstrate that conducting properties of LaAlO$_3$/SrTiO$_3$(001) heterointerfaces strongly depend on termination of LaAlO$_3$ (001) surface. We argue that both the polar "catastrophe" and the polar distortion scenarios may be realized depending on the interface stoichiometry. Our calculations predict that heterointerface…
A Comparative Ab Initio Thermodynamic Study of Oxygen Vacancies in ZnO and SrTiO3: Emphasis on Phonon Contribution
Using a hybrid Hartree–Fock (HF)-DFT method combined with LCAO basis set and periodic supercell approach, the atomic, electronic structure and phonon properties of oxygen vacancies in ZnO and SrTiO3 were calculated and compared. The important role of a ghost basis function centered at the vacant site and defect spin state for SrTiO3 is discussed. It is shown that the use of hybrid functionals is vital for correct reproduction of defects basic properties. The Gibbs free energy of formation of oxygen vacancies and their considerable temperature dependence has been compared for the two oxides. These calculations were based on the polarizability model for the soft mode temperature behavior in S…