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

Journal Article · Mon Jun 15 00:00:00 EDT 2015 · AIP Advances

DOI:https://doi.org/10.1063/1.4923320· OSTI ID:22493921

Ma, H. J. Harsan,; Ariando, ^[1]; Venkatesan, T. ^[1]; Wang, S. J. ^[2]

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1. NUSNNI-Nanocore, National University of Singapore, 117411 Singapore (Singapore)
2. Department of Physics, National University of Singapore, 117542 Singapore (Singapore)

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.

• OSTI ID: 22493921
• Journal Information: AIP Advances, Vol. 5, Issue 6; Other Information: (c) 2015 Author(s); Country of input: International Atomic Energy Agency (IAEA); ISSN 2158-3226
• Country of Publication: United States
• Language: English

Related Subjects

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