Metal-insulator transition at the LaAlO3/SrTiO3 interface revisited: A hybrid functional study

Abstract

We investigate the electronic properties of the LaAlO3/SrTiO3 interface using density functional theory. In contrast to previous studies, which relied on (semi-)local functionals and the GGA+U method, we here use a recently developed hybrid functional to determine the electronic structure. This approach offers the distinct advantage of accessing both the metallic and insulating multilayers on a parameter-free equal footing. As compared to calculations based on semilocal GGA functionals, our hybrid functional calculations lead to a considerably increased band gap for the insulating systems. The details of the electronic structure show substantial deviations from those obtained by GGA calculations. This casts severe doubts on all previous results based on semilocal functionals. In particular, corrections using rigid band shifts ("scissors operator") cannot lead to valid results.

6 pages, 4 figures

References in corpus (6)

• Magnetic effects at the interface between nonmagnetic oxides
• Avoiding the polarization catastrophe in LaAlO3 overlayers on SrTiO3(001) through a polar distortion
• Magnetism and superconductivity at LAO/STO-interfaces: the role of Ti 3d interface electrons
• Oxygen vacancies at titanate interfaces: two-dimensional magnetism and orbital reconstruction
• Field-Effect Devices Utilizing LaAlO${}_3$-SrTiO${}_3$ Interfaces
• Surface Effects on Oxide Heterostructures

Cited by in corpus (6)

• First-principles studies of multiferroic and magnetoelectric materials
• Multi-band theory of superconductivity at the LaAlO${}_3$/SrTiO${}_3$ interface
• Electronic properties of LaAlO3/SrTiO3 n-type interfaces: A GGA+U study
• Oxygen vacancies and hydrogen doping in LaAlO3/SrTiO3 heterostructures: electronic properties and impact on surface and interface reconstruction
• The mechanism of spin-orbit coupling in a 2D oxide interface
• Analysis of electronic and structural properties of surfaces and interfaces based on LaAlO3 and SrTiO3