Origin of two-dimensional electron gases at oxide interfaces: insights from theory

Abstract

The response of oxide thin films to polar discontinuities at interfaces and surfaces has generated an enormous activity due to the variety of interesting effects it gives rise to. A case in point is the discovery of the electron gas at the interface between LaAlO3 and SrTiO3, which has since been shown to be quasi-two-dimensional, switchable, magnetic and/or superconducting. Despite these findings, the origin of the two-dimensional electron gas is highly debated and several possible mechanisms remain. Here we review the main proposed mechanisms and attempt to model expected effects in a quantitative way with the ambition of better constraining what effects can/cannot explain the observed phenomenology. We do it in the framework of a phenomenological model for understanding electronic and/or redox screening of the chemical charge in oxide heterostructures. We also discuss the effect of intermixing, both conserving and non-conserving the total stoichiometry.

arXiv comment34 pages, 9 figures

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Cited by in corpus (35)

• Physics of ultrathin films and heterostructures of rare earth nickelates
• Oxide spin-orbitronics: spin-charge interconversion and topological spin textures
• Second-principles method including electron and lattice degrees of freedom
• Transparent perovskite barium stannate with high electron mobility and thermal stability
• Atomically flat single terminated oxide substrate surfaces
• Emergence of one-dimensional wires of free carriers in transition-metal-dichalcogenide nanostructures
• Engineering polar discontinuities in honeycomb lattices
• The Effect of Polar Fluctuation and Lattice Mismatch on Carrier Mobility at Oxide Interfaces
• Two-dimensional electron gas at the PbTiO${}_3$/SrTiO${}_3$ interface: an ab initio study
• Model of two-dimensional electron gas formation at ferroelectric interfaces
• Spin-texture induced by oxygen vacancies in Strontium perovskites (001) surfaces: A theoretical comparison between SrTiO3 and SrHfO3
• Electronic properties of LaAlO3/SrTiO3 n-type interfaces: A GGA+U study
• Elucidating the Influence of Native Defects on Electrical and Optical Properties in Semiconducting Oxides: An Experimental and Theoretical Investigation
• Oxygen vacancies and hydrogen doping in LaAlO3/SrTiO3 heterostructures: electronic properties and impact on surface and interface reconstruction
• Electrostatics and domains in ferroelectric superlattices
• Strain-induced polar discontinuities in two-dimensional materials from combined first-principles and Schrödinger-Poisson simulations
• Ferroelectric control of spin-polarized two-dimensional electron gas
• Influence of the ferroelectric quantum critical point on SrTiO${}_3$ interfaces
• Probing Quantum Confinement and Electronic Structure at Polar Oxide Interfaces
• Temperature-Dependent Band Structure of SrTiO${}_3$ Interfaces
• Possible Flexoelectric Origin of the Lifshitz Transition in LaAlO${}_3$/SrTiO${}_3$ Interfaces
• Metallic interface in non-SrTiO3 based titanate superlattice
• Structural and electronic phenomena at oxyfluoride KTaO${}_3$/K$M$F${}_3$ ($M$ = Zn and Ni) superlattices: Rashba splitting and 2DEG
• Evolution of domain structure with electron doping in ferroelectric thin films
• Electrical permittivity driven metal-insulator transition in heterostructures of nonpolar Mott- and band insulators
• BinPo: An open-source code to compute the band structure of two-dimensional electron systems
• Mechanism for Switchability in Electron-Doped Ferroelectric Interfaces
• Polarity-field driven conductivity in SrTiO${}_3$/LaAlO${}_3$: a hybrid functional study
• Spintronic Quantum Phase Transition in a $Graphene/P{b}_{0.24}S{n}_{0.76}Te$ Heterostructure with Giant Rashba Spin-Orbit Coupling
• Influence of a Realistic Multiorbital Band Structure on Conducting Domain Walls in Perovskite Ferroelectrics
• Magnetotransport in graphene/Pb0.24Sn0.76Te heterostructures: finding a way to avoid catastrophe
• Polarization discontinuity driven two dimensional electron gas at A${}_2$Mo${}_3$O${}_8$/B${}_2$Mo${}_3$O${}_8$ (A, B : Zn,Mg,Cd) interfaces
• Bound States at Semiconductor -- Mott Insulator Interfaces
• Multiferroic interfaces composed of d0 perovskites oxides
• Coupling between tilts and charge carriers at polar-nonpolar perovskite interfaces