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Title: Tunable one-dimensional electron gas carrier densities at nanostructured oxide interfaces

Journal Article · · Scientific Reports
DOI:https://doi.org/10.1038/srep25452· OSTI ID:1255663
 [1];  [1];  [2];  [2];  [2];  [2]
  1. Univ. of Tennessee, Knoxville, TN (United States)
  2. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

The emergence of two-dimensional metallic states at the LaAlO3/SrTiO3 (LAO/STO) heterostructure interface is known to occur at a critical thickness of four LAO over layers. This insulator-to-metal transition can be explained through the polar catastrophe mechanism arising from the divergence of the electrostatic potential at the LAO surface. Here, we demonstrate that nanostructuring can be effective in reducing or eliminating this critical thickness. Employing a modified polar catastrophe" model, we demonstrate that the nanowire heterostructure electrostatic potential diverges more rapidly as a function of layer thickness than in a regular heterostructure. Our first principles calculations indicate that for nanowire heterostructure geometries a one-dimensional electron gas (1DEG) can be induced, consistent with recent experimental observations of 1D conductivity in LAO/STO steps. Similar to LAO/STO 2DEGs, we predict that the 1D charge density will decay laterally within a few unit cells away from the nanowire; thus providing a mechanism for tuning the carrier behavior between 1D and 2D conductivity. Furthermore, our work provides insight into the creation and manipulation of charge density at an oxide heterostructure interface and therefore may be beneficial for future nanoelectronic devices and for the engineering of novel quantum phases.

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE
Grant/Contract Number:
AC05-00OR22725
OSTI ID:
1255663
Journal Information:
Scientific Reports, Vol. 6; ISSN 2045-2322
Publisher:
Nature Publishing GroupCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 6 works
Citation information provided by
Web of Science

References (49)

Emergent phenomena at oxide interfaces journal January 2012
Interface Physics in Complex Oxide Heterostructures journal March 2011
Oxide Interfaces--An Opportunity for Electronics journal March 2010
Oxide Nanoelectronics on Demand journal February 2009
MATERIALS SCIENCE: Atomically Engineered Oxide Interfaces journal February 2009
Mechanical Tuning of LaAlO 3 /SrTiO 3 Interface Conductivity journal April 2015
Anomalous High Mobility in LaAlO 3 /SrTiO 3 Nanowires journal January 2013
Switchable Induced Polarization in LaAlO 3 /SrTiO 3 Heterostructures journal January 2012
Creation of High Mobility Two-Dimensional Electron Gases via Strain Induced Polarization at an Otherwise Nonpolar Complex Oxide Interface journal February 2015
Tuning the Interface Conductivity of LaAlO 3 /SrTiO 3 Using Ion Beams: Implications for Patterning journal November 2013
A high-mobility electron gas at the LaAlO3/SrTiO3 heterointerface journal January 2004
Tunable Quasi-Two-Dimensional Electron Gases in Oxide Heterostructures journal September 2006
Magnetic effects at the interface between non-magnetic oxides journal June 2007
Superconducting Interfaces Between Insulating Oxides journal August 2007
Why some interfaces cannot be sharp journal January 2006
First-Principles Modeling of Electrostatically Doped Perovskite Systems journal March 2011
Berry-phase theory of polar discontinuities at oxide-oxide interfaces journal December 2009
One-Dimensional Quantum Wire Formed at the Boundary between Two Insulating LaAlO 3 / SrTiO 3 Interfaces journal March 2014
Tunable conductivity threshold at polar oxide interfaces journal January 2012
Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set journal October 1996
Projector augmented-wave method journal December 1994
From ultrasoft pseudopotentials to the projector augmented-wave method journal January 1999
Generalized Gradient Approximation Made Simple journal October 1996
Electron-energy-loss spectra and the structural stability of nickel oxide: An LSDA+U study journal January 1998
Ionic relaxation contribution to the electronic reconstruction at the n -type LaAlO 3 / SrTiO 3 interface journal November 2008
Exponential decay of relaxation effects at LaAlO3/SrTiO3 heterointerfaces journal January 2009
Surface effects on oxide heterostructures journal November 2007
Avoiding the Polarization Catastrophe in LaAlO 3 Overlayers on SrTiO 3 ( 001 ) through Polar Distortion journal March 2009
Special points for Brillouin-zone integrations journal June 1976
Electron Transfer and Ionic Displacements at the Origin of the 2D Electron Gas at the LAO/STO Interface: Direct Measurements with Atomic-Column Spatial Resolution journal June 2012
Origin of Charge Density at LaAlO3 on SrTiO3 Heterointerfaces: Possibility of Intrinsic Doping journal May 2007
Lattice Relaxation in Oxide Heterostructures: LaTiO 3 / SrTiO 3 Superlattices journal July 2006
Electronic reconstruction at an interface between a Mott insulator and a band insulator journal April 2004
Electronic charges and electric potential at LaAlO 3 /SrTiO 3 interfaces studied by core-level photoemission spectroscopy journal December 2011
Creation and control of a two-dimensional electron liquid at the bare SrTiO3 surface journal January 2011
Transparent conducting oxides: A δ-doped superlattice approach journal August 2014
Fractionally δ-Doped Oxide Superlattices for Higher Carrier Mobilities journal January 2012
Enhanced carrier mobilities in two-dimensional electron gases at III-III/I-V oxide heterostructure interfaces journal June 2012
Thickness-dependent carrier density at the surface of SrTiO 3 (111) slabs journal February 2014
Oxide superlattices with alternating p and n interfaces journal July 2009
Lattice-polarization effects on electron-gas charge densities in ionic superlattices journal May 2006
Theory of Mott insulator–band insulator heterostructures journal August 2004
Two-dimensional electron gas with universal subbands at the surface of SrTiO3 journal January 2011
LaTiO 3 /KTaO 3 interfaces: A new two-dimensional electron gas system journal March 2015
Correction to Creation of High Mobility Two-Dimensional Electron Gases via Strain Induced Polarization at an Otherwise Nonpolar Complex Oxide Interface journal March 2017
The net charge at interfaces between insulators journal February 2011
Subband Structure of a Two-Dimensional Electron Gas Formed at the Polar Surface of the Strong Spin-Orbit Perovskite KTaO 3 journal March 2012
Oxide superlattices with alternating p and n interfaces text January 2009
Berry-phase theory of polar discontinuities at oxide-oxide interfaces text January 2009

Cited By (4)

Oxygen Diode Formed in Nickelate Heterostructures by Chemical Potential Mismatch journal March 2018
Formation and Tuning of 2D Electron Gas in Perovskite Heterostructures journal December 2019
Surface termination and electronic reconstruction in YBa 2 Cu 3 O 7 δ journal August 2018
Tunable 2D electron gas at the LaAlO 3 / SrTiO 3 ( 001 ) interface journal July 2019