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Title: Temperature dependence of photoluminescence spectra of bilayer two-dimensional electron gases in LaAlO{sub 3}/SrTiO{sub 3} superlattices: coexistence of Auger recombination and single-carrier trapping

We report emerging photoluminescence (PL) of bilayer two-dimensional electron gases (2DEG) in LaAlO{sub 3}/SrTiO{sub 3} (LAO/STO) systems. A strong blue PL emerges in bilayer-2DEGs in LAO/STO/LAO/STO which doesn’t show in LAO/STO. PL band in bilayer-2DEGs includes both nearly temperature independent Auger recombination and temperature dependent free electron trapping while it crossovers from Auger recombination to single carrier trapping in LAO/STO. The PL signal of free electron trapping appears at high temperatures and it is much stronger than Auger recombination in the conducting channel in bilayer 2DEGs. This observation shows that high mobility carriers dominate the carrier dynamics in bilayer-2DEGs in LAO/STO superlattices.
Authors:
;  [1] ;  [2] ;  [1] ;  [2] ;  [2] ;  [3] ;  [4]
  1. NUSNNI-Nanocore, National University of Singapore, 117411 Singapore (Singapore)
  2. (Singapore)
  3. Department of Physics, National University of Singapore, 117542 Singapore (Singapore)
  4. (IMRE), A*STAR (Agency for Science, Technology and Research), 3 Research Link, Singapore 117602 (Singapore)
Publication Date:
OSTI Identifier:
22493921
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Advances; Journal Volume: 5; Journal Issue: 6; 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; ALUMINATES; AUGER EFFECT; CHARGE CARRIERS; ELECTRONS; EMISSION SPECTROSCOPY; LANTHANUM OXIDES; LAYERS; MOBILITY; PHOTOLUMINESCENCE; RECOMBINATION; STRONTIUM TITANATES; SUPERLATTICES; TEMPERATURE DEPENDENCE; TRAPPING; TWO-DIMENSIONAL SYSTEMS