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Title: Individual electron and hole localization in submonolayer InN quantum sheets embedded in GaN

Abstract

We investigate sub-monolayer InN quantum sheets embedded in GaN(0001) by temperature-dependent photoluminescence spectroscopy under both continuous-wave and pulsed excitation. Both the peak energy and the linewidth of the emission band associated with the quantum sheets exhibit an anomalous dependence on temperature indicative of carrier localization. Photoluminescence transients reveal a power law decay at low temperatures reflecting that the recombining electrons and holes occupy spatially separate, individual potential minima reminiscent of conventional (In,Ga)N(0001) quantum wells exhibiting the characteristic disorder of a random alloy. At elevated temperatures, carrier delocalization sets in and is accompanied by a thermally activated quenching of the emission. We ascribe the strong nonradiative recombination to extended states in the GaN barriers and confirm our assumption by a simple rate-equation model.

Authors:
; ; ; ; ;  [1]
  1. Paul-Drude-Institut für Festkörperelektronik, Leibniz-Institut im Forschungsverbund Berlin e. V., Hausvogteiplatz 5–7, 10117 Berlin (Germany)
Publication Date:
OSTI Identifier:
22594373
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 109; Journal Issue: 4; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; ALLOYS; ELECTRONS; EXCITATION; GALLIUM NITRIDES; HOLES; INDIUM NITRIDES; LINE WIDTHS; PHOTOLUMINESCENCE; QUANTUM WELLS; QUENCHING; REACTION KINETICS; SHEETS; SPECTROSCOPY; TEMPERATURE DEPENDENCE; TEMPERATURE RANGE 0065-0273 K

Citation Formats

Feix, F., E-mail: feix@pdi-berlin.de, Flissikowski, T., Chèze, C., Calarco, R., Grahn, H. T., and Brandt, O. Individual electron and hole localization in submonolayer InN quantum sheets embedded in GaN. United States: N. p., 2016. Web. doi:10.1063/1.4960006.
Feix, F., E-mail: feix@pdi-berlin.de, Flissikowski, T., Chèze, C., Calarco, R., Grahn, H. T., & Brandt, O. Individual electron and hole localization in submonolayer InN quantum sheets embedded in GaN. United States. doi:10.1063/1.4960006.
Feix, F., E-mail: feix@pdi-berlin.de, Flissikowski, T., Chèze, C., Calarco, R., Grahn, H. T., and Brandt, O. Mon . "Individual electron and hole localization in submonolayer InN quantum sheets embedded in GaN". United States. doi:10.1063/1.4960006.
@article{osti_22594373,
title = {Individual electron and hole localization in submonolayer InN quantum sheets embedded in GaN},
author = {Feix, F., E-mail: feix@pdi-berlin.de and Flissikowski, T. and Chèze, C. and Calarco, R. and Grahn, H. T. and Brandt, O.},
abstractNote = {We investigate sub-monolayer InN quantum sheets embedded in GaN(0001) by temperature-dependent photoluminescence spectroscopy under both continuous-wave and pulsed excitation. Both the peak energy and the linewidth of the emission band associated with the quantum sheets exhibit an anomalous dependence on temperature indicative of carrier localization. Photoluminescence transients reveal a power law decay at low temperatures reflecting that the recombining electrons and holes occupy spatially separate, individual potential minima reminiscent of conventional (In,Ga)N(0001) quantum wells exhibiting the characteristic disorder of a random alloy. At elevated temperatures, carrier delocalization sets in and is accompanied by a thermally activated quenching of the emission. We ascribe the strong nonradiative recombination to extended states in the GaN barriers and confirm our assumption by a simple rate-equation model.},
doi = {10.1063/1.4960006},
journal = {Applied Physics Letters},
number = 4,
volume = 109,
place = {United States},
year = {Mon Jul 25 00:00:00 EDT 2016},
month = {Mon Jul 25 00:00:00 EDT 2016}
}
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