Origin of Metallic States at Heterointerface between Band Insulators LaAlO${}_3$ and SrTiO${}_3$

Abstract

We have studied the electronic structure at the heterointerface between the band insulators LaAlO${}_3$ and SrTiO${}_3$ using $insitu$ photoemission spectroscopy. Our experimental results clearly reveal the formation of a notched structure on the SrTiO${}_3$ side due to band bending at the metallic LaAlO${}_3$/TiO${}_2$-SrTiO${}_3$ interface. The structure, however, is absent at the insulating LaAlO${}_3$/SrO-SrTiO${}_3$ interface. The present results indicate that the metallic states originate not from the charge transfer through the interface on a short-range scale but from the accumulation of carriers on a long-range scale.

arXiv comment20 pages, 4 figures

References in corpus (8)

• Why Some Interfaces Cannot be Sharp
• 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
• Photoemission from buried interfaces in SrTiO3/LaTiO3 superlattices
• Lattice polarization effects on electron-gas charge densities in ionic superlattices
• Electronic properties of buried hetero-interfaces of LaAlO3 on SrTiO3
• Photoemission Spectral Weight Transfer and Mass Renormalization in the Fermi-Liquid System La${}_{1-x}$Sr${}_x$TiO${}_{3+y/2}$

Cited by in corpus (34)

• Profiling the interface electron gas of LaAlO3/SrTiO3 heterostructures by hard X-ray photoelectron spectroscopy
• Instability, Intermixing and Electronic Structure at the Epitaxial LaAlO3/SrTiO3(001) Heterojunction
• Built-in and induced polarization across LaAlO${}_3$/SrTiO${}_3$ heterojunctions
• "Water-cycle" mechanism for writing and erasing nanostructures at the LaAlO3/SrTiO3 interface
• Control of electronic conduction at an oxide heterointerface using surface polar adsorbates
• Surface defects and conduction in polar oxide heterostructures
• Polarity-induced oxygen vacancies at LaAlO3|SrTiO3 interfaces
• Polar catastrophe and electronic reconstructions at the LaAlO3/SrTiO3 interface: evidence from optical second harmonic generation
• A variational pseudo-self-interaction correction approach: ab-initio description of correlated oxides and molecules
• Upper limit to magnetism in LaAlO3/SrTiO3 heterostructures
• Hard x-ray photoemission and density functional theory study of the internal electric field in SrTiO3/LaAlO3 oxide heterostructures
• Electronic charges and electric potential at LaAlO3/SrTiO3 interfaces studied by core-level photoemission spectroscopy
• Ferroelectric Dead Layer Driven by a Polar Interface
• Band offsets and density of Ti3+ states probed by X-ray photoemission on LaAlO3/SrTiO3 heterointerfaces and their LaAlO3 and SrTiO3 bulk precursors
• Prediction of a spin-polarized two-dimensional electron gas at the LaAlO3/EuO(001) interface
• Interface relaxation and electrostatic charge depletion in the oxide heterostructure LaAlO3/SrTiO3
• Enhanced persistent photoconductivity in $\delta$-doped LaAlO${}_3$/SrTiO${}_3$ heterostructures
• Oxygen Electromigration and Energy Band Reconstruction Induced by Electrolyte Field Effect at Oxide Interfaces
• Optically excited multi-band conduction in LaAlO3/SrTiO3 heterostructures
• Quantum confinement in perovskite oxide heterostructures: tight binding instead of nearly free electron picture
• Electronic structure of the SrTiO${}_3$/LaAlO${}_3$ interface revealed by resonant soft x-ray scattering
• Oxygen Vacancies on SrO-terminated SrTiO3(001) Surfaces studied by Scanning Tunneling Spectroscopy
• Microscopic understanding of the orbital splitting and its tuning at oxide interfaces
• Anomalous response to gate voltage application in mesoscopic LaAlO_3/SrTiO_3 devices
• First-Principles Modeling of Pt/LaAlO3/SrTiO3 Capacitors Under an External Bias Potential
• Polarization screening and induced carrier density at the interface of LaAlO${}_3$ overlayer on SrTiO${}_3$ (001)
• Macroscopic description of the two-dimensional LaAlO${}_3$/SrTiO${}_3$ interface
• Observation of strontium segregation in LaAlO${}_3$/SrTiO${}_3$ and NdGaO${}_3$/SrTiO${}_3$ oxide heterostructures by X-ray photoemission spectroscopy
• Superconducting tunneling spectroscopy of spin-orbit coupling and orbital depairing in Nb:SrTiO${}_3$
• Polaronic nature of a muonium-related paramagnetic center in SrTiO${}_3$
• Transport and thermoelectric properties of the LaAlO${}_3$/SrTiO${}_3$ interface
• Conducting and insulating LaAlO${}_3$/SrTiO${}_3$ interfaces: A comparative surface photovoltage investigation
• In situ investigation of conducting interface formation in LaAlO3/SrTiO3 heterostructure
• General considerations of the electrostatic boundary conditions in oxide heterostructures