Lattice polarization effects on electron-gas charge densities in ionic superlattices

Abstract

The atomic-level control achievable in artificially-structured oxide superlattices provides a unique opportunity to explore interface phases of matter including high-density 2D electron gases. Electronic-structure calculations show that the charge distribution of the 2D gas is strongly modulated by electron-phonon interactions with significant ionic polarization. Anharmonic finite-temperature effects must be included to reproduce experiment. Density functional perturbation theory is used to parameterize a simple model introduced to represent these effects and predict temperature dependencies.

16 pages including figures Added references 5 and 24, structure picture to Fig. 4, and new paragraph at end of Sec. III

References in corpus (5)

• Phonons and related properties of extended systems from density-functional perturbation theory
• Tunability of the dielectric response of epitaxially strained SrTiO3 from first principles
• Spatial inhomogeneity and strong correlation physics: a dynamical mean field study of a model Mott-insulator/band-insulator heterostructure
• Comparison of Global and Local Adaptive Coordinates for Density Functional Calculations
• Theory of Mott insulator/band insulator heterostructure

Cited by in corpus (33)

• Magnetic effects at the interface between nonmagnetic oxides
• High-temperature interface superconductivity between metallic and insulating cuprates
• Suppression of Octahedral Tilts and Associated Changes of Electronic Properties at Epitaxial Oxide Heterostructure Interfaces
• Avoiding the polarization catastrophe in LaAlO3 overlayers on SrTiO3(001) through a polar distortion
• Dominant mobility modulation by the electric field effect at the LaAlO_3 / SrTiO_3 interface
• Half-metallic semiDirac point generated by quantum confinement in TiO${}_2$/VO${}_2$ nanostructures
• Lattice relaxation, electronic screening, and spin and orbital phase diagram of LaTiO${}_3$/SrTiO${}_3$ superlattices
• Polar Discontinuity Doping of the LaVO_3/SrTiO_3 Interface
• Origin of Metallic States at Heterointerface between Band Insulators LaAlO${}_3$ and SrTiO${}_3$
• Termination Control of the Interface Dipole in La${}_{0.7}$Sr${}_{0.3}$MnO${}_3$/Nb:SrTiO${}_3$ (001) Schottky Junctions
• Nature of weak magnetism in SrTiO3/LaAlO3 multilayers
• Two Dimensional Spin-Polarized Electron Gas at the Oxide Interfaces
• The Mott insulator LaTiO_3 in heterostructures with SrTiO_3 is metallic
• Temperature Dependent Polarity Reversal in Au/Nb:SrTiO3 Schottky Junctions
• Spin responses and effective Hamiltonian for the two dimensional electron gas at oxide interface {LaAlO}${}_3$/{SrTiO}${}_3$
• Interface relaxation and electrostatic charge depletion in the oxide heterostructure LaAlO3/SrTiO3
• Exponential decay of relaxation effects at LaAlO3/SrTiO3 heterointerfaces
• Enhanced two dimensional electron gas charge densities at III-III/I-V oxide heterostructure interfaces
• Strongly renormalized quasi-two-dimensional electron gas in a heterostructure with correlation effects
• Optically tuned dimensionality crossover in photocarrier-doped SrTiO${}_3$: onset of weak localization
• Direct spectroscopic observation of a shallow hydrogen-like donor state in insulating SrTiO${}_3$
• Tunable 2-dimensional/3-dimensional electron gases by submonolayer La doping of SrTiO_{3}
• Electronic Interface Reconstruction at Polar-Nonpolar Mott Insulator Heterojunctions
• Thickness Dependent Carrier Density at the Surface of SrTiO3 (111) Slabs
• Structural relaxation and metal-insulator transition at the interface between SrTiO3 and LaAlO3
• Formation of orbital-selective electron states in LaTiO${}_3$/SrTiO${}_3$ superlattices
• Engineered Kondo screening and nonzero Berry phase in SrTiO3/LaTiO3/SrTiO3 heterostructures
• Oxide tunnel junctions supporting a two-dimensional electron gas
• Lattice screening of the polar catastrophe and hidden in-plane polarization in KNbO${}_3$/BaTiO${}_3$ interfaces
• Electronic and magnetic properties in strongly correlated heterostructures
• Electrical permittivity driven metal-insulator transition in heterostructures of nonpolar Mott- and band insulators
• Graded Orbital Occupation near Interfaces in a La2NiO4 - La2CuO4 Superlattice
• Role of multiple subband renormalization in the electronic transport of correlated oxide superlattices