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Title: Towards enhancing two-dimensional electron gas quantum confinement effects in perovskite oxide heterostructures

We explore the possibility of achieving highly confined two-dimensional electron gas (2DEG) within one single atomic layer through a comprehensive comparison study on three prototypical perovskite heterostructures, LaAlO{sub 3}/ATiO{sub 3} (A = Ca, Sr, and Ba), using first-principles electronic structure calculations. We predict that the heterostructure LaAlO{sub 3}/BaTiO{sub 3} has a highly confined 2DEG within a single atomic layer of the substrate BaTiO{sub 3}, and exhibits relatively higher interfacial charge carrier density and larger magnetic moments than the well-known LaAlO{sub 3}/SrTiO{sub 3} system. The long Ti-O bond length in the ab-plane of the LaAlO{sub 3}/BaTiO{sub 3} heterostructure is responsible for the superior charge confinement. We propose BaTiO{sub 3} as an exceptional substrate material for 2DEG systems with potentially superior properties.
Authors:
; ;  [1]
  1. Department of NanoEngineering, University of California, San Diego, 9500 Gilman Drive, Mail Code 0448, La Jolla, California 92093-0448 (United States)
Publication Date:
OSTI Identifier:
22399321
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 117; Journal Issue: 11; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; ALUMINATES; BARIUM COMPOUNDS; BOND LENGTHS; CALCIUM COMPOUNDS; CHARGE CARRIERS; COMPARATIVE EVALUATIONS; CUBIC LATTICES; ELECTRON GAS; ELECTRONIC STRUCTURE; INTERFACES; LANTHANUM COMPOUNDS; LAYERS; MAGNETIC MOMENTS; PEROVSKITE; STRONTIUM TITANATES; SUBSTRATES; TWO-DIMENSIONAL SYSTEMS