Electronic properties of LaAlO3/SrTiO3 n-type interfaces: a GGA+U study. (27th January 2017)

• Record Type: Journal Article
• Authors: Piyanzina, I I; Kopp, T; Lysogorskiy, Yu V; Tayurskii, D A; Eyert, V
• Is Part Of: Journal of physics. Volume 29:Number 9(2017)
• Publication Date: 2017-01-27
• Subjects: LAO/STO heterostructure -- electronic structure -- GGA+U; Condensed matter -- Periodicals; Matière condensée -- Périodiques; Vaste stoffen; Vloeistoffen; Natuurkunde; Electronic journals; Computer network resources; 530.4105
• DOI: 10.1088/1361-648X/aa57ac
• Languages: English
• ISSNs: 0953-8984

Abstract

Abstract: The role of electronic correlation effects for a realistic description of the electronic properties of L a A l O 3 / S r T i O 3 heterostructures as covered by the on-site Coulomb repulsion within the GGA+ U approach is investigated. Performing a systematic variation of the values of the Coulomb parameters applied to the Ti 3 d and La 4 f orbitals we put previous suggestions to include a large value for the La 4 f states into perspective. Furthermore, our calculations provide deeper insight into the band gap landscape in the space spanned by these Coulomb parameters and the resulting complex interference effects. In addition, we identify important correlations between the local Coulomb interaction within the La 4 f shell, the band gap, and the atomic displacements at the interface. In particular, these on-site Coulomb interactions influence buckling within the LaO interface layer, which via its strong coupling to the electrostatic potential in the LAO overlayer causes considerable shifts of the electronic states at the surface and eventually controls the band gap.