Microscopic understanding of the orbital splitting and its tuning at oxide interfaces

Abstract

By means of a Wannier projection within the framework of density functional theory, we are able to identify the modified c-axis hopping and the energy mismatch between the cation bands as the main source of the $t_{2g}$ splitting around the $\Gamma$ point for oxide heterostructures, excluding previously proposed mechanisms such as Jahn-Teller distortions or electric field asymmetries. Interfacing LaAlO${}_3$, LaVO${}_3$, SrVO${}_3$ and SrNbO${}_3$ with SrTiO${}_3$ we show how to tune this orbital splitting, designing heterostructures with more $d_{xy}$ electrons at the interface. Such an "orbital engineering" is the key for controlling the physical properties at the interface of oxide heterostructures.

4.5 pages, 4 figures, submitted on May 9. 2012 to Physical Review. PDF Supplementary material containing tables of hopping and energy levels for the different heterostructures

References in corpus (6)

• Direct imaging of the coexistence of ferromagnetism and superconductivity at the LaAlO3/SrTiO3 interface
• Orbital order and possible superconductivity in LaNiO3/LaMO3 superlattices
• Polar Discontinuity Doping of the LaVO_3/SrTiO_3 Interface
• Origin of Metallic States at Heterointerface between Band Insulators LaAlO${}_3$ and SrTiO${}_3$
• Polarity-induced oxygen vacancies at LaAlO3|SrTiO3 interfaces
• Electronic structure induced reconstruction and magnetic ordering at the LaAlO${}_3|$SrTiO${}_3$ interface

Cited by in corpus (11)

• Theory of spin-orbit coupling at LaAlO3/SrTiO3 interfaces and SrTiO3 surfaces
• Tuning the work function in transition metal oxides and their heterostructures
• Ab initio study of the two-dimensional metallic state at the surface of SrTiO3: importance of oxygen vacancies
• Anomalous orbital structure in a spinel-perovskite interface $\gamma$-Al${}_2$O${}_3$/SrTiO${}_3$
• Phase diagrams of voltage-gated oxide interfaces with strong Rashba coupling
• Quantum confinement in perovskite oxide heterostructures: tight binding instead of nearly free electron picture
• Boosting the power factor with resonant states: a model study
• Large enhancement of the thermoelectric power factor in disordered materials through resonant scattering
• Electrical permittivity driven metal-insulator transition in heterostructures of nonpolar Mott- and band insulators
• A comparative DMFT study of the eg-orbital Hubbard model in thin films
• Quantized electronic fine structure with large anisotropy in ferromagnetic Fe films