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Title: LaTiO{sub 3}/KTaO{sub 3} interfaces: A new two-dimensional electron gas system

We report a new 2D electron gas (2DEG) system at the interface between a Mott insulator, LaTiO{sub 3}, and a band insulator, KTaO{sub 3}. For LaTiO{sub 3}/KTaO{sub 3} interfaces, we observe metallic conduction from 2 K to 300 K. One serious technological limitation of SrTiO{sub 3}-based conducting oxide interfaces for electronics applications is the relatively low carrier mobility (0.5-10 cm{sup 2}/V s) of SrTiO{sub 3} at room temperature. By using KTaO{sub 3}, we achieve mobilities in LaTiO{sub 3}/KTaO{sub 3} interfaces as high as 21 cm{sup 2}/V s at room temperature, over a factor of 3 higher than observed in doped bulk SrTiO{sub 3}. By density functional theory, we attribute the higher mobility in KTaO{sub 3} 2DEGs to the smaller effective mass for electrons in KTaO{sub 3}.
Authors:
; ; ;  [1] ; ;  [2] ;  [2] ;  [3]
  1. Department of Applied Physics and Center for Research on Interface Structures and Phenomena (CRISP), Yale University, New Haven, Connecticut 06520 (United States)
  2. Brookhaven National Laboratory, Center for Functional Nanomaterials, Upton, New York 11973 (United States)
  3. (China)
Publication Date:
OSTI Identifier:
22415259
Resource Type:
Journal Article
Resource Relation:
Journal Name: APL materials; Journal Volume: 3; Journal Issue: 3; Other Information: (c) 2015 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CARRIER MOBILITY; DENSITY FUNCTIONAL METHOD; DOPED MATERIALS; EFFECTIVE MASS; ELECTRIC CONDUCTIVITY; ELECTRON GAS; INTERFACES; LANTHANUM COMPOUNDS; POTASSIUM COMPOUNDS; STRONTIUM TITANATES; TANTALATES; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0273-0400 K; TWO-DIMENSIONAL SYSTEMS