Oxygen vacancies at titanate interfaces: two-dimensional magnetism and orbital reconstruction

Abstract

We show that oxygen vacancies at titanate interfaces induce a complex multiorbital reconstruction which involves a lowering of the local symmetry and an inversion of t2g and eg orbitals resulting in the occupation of the eg orbitals of Ti atoms neighboring the O vacancy. The orbital reconstruction depends strongly on the clustering of O vacancies and can be accompanied by a magnetic splitting between the local eg orbitals with lobes directed towards the vacancy and interface dxy orbitals. The reconstruction generates a two-dimensional interface magnetic state not observed in bulk SrTiO3. Using generalized gradient approximation (LSDA) with intra-atomic Coulomb repulsion (GGA+U), we find that this magnetic state is common for titanate surfaces and interfaces.

13 pages, 18 figures, to appear in Physical Review B

References in corpus (26)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• Magnetic effects at the interface between nonmagnetic oxides
• Direct imaging of the coexistence of ferromagnetism and superconductivity at the LaAlO3/SrTiO3 interface
• Coexistence of Magnetic Order and Two-dimensional Superconductivity at LaAlO${}_3$/SrTiO${}_3$ Interfaces
• The role of oxygen vacancies in SrTiO3 at the LaAlO3/SrTiO3 interface
• High Mobility in LaAlO3/SrTiO3 Heterostructures: Origin, Dimensionality and Perspectives
• Origin of charge density at LaAlO3-on-SrTiO3 hetero-interfaces; possibility of intrinsic doping
• Coexistence of superconductivity and ferromagnetism in two dimensions
• A possible path to a new class of ferromagnetic and half metallic ferromagnetic materials
• Mapping the Spatial Distribution of Charge Carriers in LaAlO3/SrTiO3 Heterostructures
• Orbital reconstruction and two-dimensional electron gas at the LaAlO3/SrTiO3 interface
• Profiling the interface electron gas of LaAlO3/SrTiO3 heterostructures by hard X-ray photoelectron spectroscopy
• Ab-initio study of SrTiO3 surfaces
• Tailoring a two-dimensional electron gas at the LaAlO3/SrTiO3 (001) interface by epitaxial strain
• Superconductivity and Ferromagnetism in Oxide Interface Structures: Possibility of Finite Momentum Pairing
• Surface defects and conduction in polar oxide heterostructures
• Magnetism and superconductivity at LAO/STO-interfaces: the role of Ti 3d interface electrons
• Polarity-induced oxygen vacancies at LaAlO3|SrTiO3 interfaces
• Two-dimensional electron liquid state at LaAlO3-SrTiO3 interfaces
• Localized vs. delocalized character of charge carriers in LaAlO3/ SrTiO3 superlattices
• A First-Principles Study of the Electronic Reconstructions of LaAlO3/SrTiO3 Heterointerfaces and Their Variants
• Anion vacancy driven magnetism in incipient ferroelectric SrTiO3 and KTaO3 nanoparticles
• Interface hole-doping in cuprate-titanate superlattices
• Structural relaxation and metal-insulator transition at the interface between SrTiO3 and LaAlO3
• Mechanism of orbital reconstruction at the interfaces of transition metal oxides
• Electronic charge and orbital reconstruction at cuprate-titanate interfaces

Cited by in corpus (47)

• Physics of SrTiO${}_3$-based heterostructures and nanostructures: a review
• A polarity-induced defect mechanism for conductivity and magnetism at polar-nonpolar oxide interfaces
• Direct k-space mapping of the electronic structure in an oxide-oxide interface
• Room-Temperature Electronically-Controlled Ferromagnetism at the LaAlO3/SrTiO3 Interface
• A Gate-tunable Polarized Phase of Two-Dimensional Electrons at the LaAlO3/SrTiO3 Interface
• Persistent Optically Induced Magnetism in Oxygen-Deficient Strontium Titanate
• Surface magnetism of strontium titanate
• The interfacial effects on the spin density wave in FeSe/SrTiO3 thin film
• Ab initio study of the two-dimensional metallic state at the surface of SrTiO3: importance of oxygen vacancies
• Localized versus itinerant states created by multiple oxygen vacancies in SrTiO3
• Spirals and skyrmions in two dimensional oxide heterostructures
• Competition Between Kondo Screening and Magnetism at the LaAlO${}_3$/SrTiO${}_3$ Interface
• Emerging magnetism and electronic phase separation at titanate interfaces
• Superconductivity with Rashba Spin-Orbit Coupling and Magnetic Field
• Topological superconductivity and Majorana bound states at the LaAlO${}_3$/SrTiO${}_3$ interface
• Absence of Giant Spin Splitting in the Two-Dimensional Electron Liquid at the Surface of SrTiO${}_3$ (001)
• High-Mobility Two-Dimensional Electron Gases at Oxide Interfaces: Origins and Opportunities
• Electron dichotomy on the SrTiO${}_3$ defect surface augmented by many-body effects
• Tuning the two-dimensional electron liquid at oxide interfaces by buffer-layer-engineered redox reactions
• Bandgap Controlling of the Oxygen-Vacancy-Induced Two-Dimensional Electron Gas in SrTiO3
• Electric-field-controllable high-spin SrRuO3 driven by a solid ionic junction
• Pair breaking in multi-orbital superconductors: an application to oxide interfaces
• Defect states and excitations in a Mott insulator with orbital degrees of freedom: Mott-Hubbard gap versus optical and transport gaps in doped systems
• Oxygen-vacancy driven electron localization and itinerancy in rutile-based TiO${}_2$
• Controlling the magnetism of oxygen surface vacancies in strontium titanate $(\mathrm{SrTi}{\mathrm{O}}_3)$ through charging
• Metal-insulator transition at the LaAlO3/SrTiO3 interface revisited: A hybrid functional study
• Oxygen vacancies and hydrogen doping in LaAlO3/SrTiO3 heterostructures: electronic properties and impact on surface and interface reconstruction
• Hidden Mott insulator in metallic PdCrO${}_2$
• Raman and fluorescence contributions to resonant inelastic soft x-ray scattering on LaAlO${}_3$/SrTiO${}_3$ heterostructures
• Fingerprints of spin-orbital polarons and of their disorder in the photoemission spectra of doped Mott insulators with orbital degeneracy
• Defects, disorder and strong electron correlations in orbital degenerate, doped Mott insulators
• From Weak Antilocalization to Kondo Scattering in a Magnetic Complex Oxide Interface
• Phase segregation of superconductivity and ferromagnetism at LaAlO${}_3$/SrTiO${}_3$ interface
• Long-range electronic reconstruction to a $d_{xz,yz}$-dominated Fermi surface below the LaAlO${}_3$/SrTiO${}_3$ interface
• Hydrostatic pressure response of an oxide two-dimensional electron system
• Nature of electrons from oxygen vacancies and polar catastrophe at LaAlO3/SrTiO3 interfaces
• Analysis of electronic and structural properties of surfaces and interfaces based on LaAlO3 and SrTiO3
• Torque magnetometry of an amorphous-alumina/strontium-titanate interface
• Magnetic 2D electron liquid at the surface of Heusler semiconductors
• The Vortex Signature of Discrete Ferromagnetic Dipoles at the LaAlO${}_3$/SrTiO${}_3$ Interface
• The interface between Sr${}_2$RuO${}_4$ and Ru-metal inclusion--Implications for its superconductivity
• Hard X-ray photoemission spectroscopy of LaVO${}_3$/SrTiO${}_3$: Band alignment and electronic reconstruction
• Spectral properties of heterostructures containing half-metallic ferromagnets in the presence of local many-body correlations
• Magnetically ordered state at correlated oxide interfaces: the role of random oxygen defects
• Oxide Heterostructures from a Realistic Many-Body Perspective
• La displacement driven Double-exchange like mediation in Titanium $d_{xy}$ ferromagnetism at the LaAlO${}_3$/SrTiO${}_3$
• Large electropositive cations as surfactants for the growth of polar epitaxial films