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Title: GaAsSb/GaAsN short-period superlattices as a capping layer for improved InAs quantum dot-based optoelectronics

Abstract

The application of a GaAsSb/GaAsN short-period superlattice capping layer (CL) on InAs/GaAs quantum dots (QDs) is shown to be an option for providing improved luminescence properties to this system. Separating both GaAsSb and GaAsN ternaries during the growth in 2 monolayer-thick phases solves the GaAsSbN immiscibility-related problems. Strong fluctuations in the CL composition and strain field as well as in the QD size distribution are significantly reduced, and a more regular CL interface is also obtained. Room-temperature (RT) photoluminescence (PL) is obtained for overall N contents as high as 3%, yielding PL peak wavelengths beyond 1.4 μm in samples with a type-II band alignment. High external quantum efficiency electroluminescence and photocurrent from the QD ground state are also demonstrated at RT in a single QD-layer p-i-n device. Thus, it becomes possible to combine and transfer the complementary benefits of Sb- and N-containing GaAs alloys to InAs QD-based optoelectronics.

Authors:
; ; ;  [1]; ; ;  [2]
  1. Institute for Systems based on Optoelectronics and Microtechnology (ISOM) and Departamento de Ingeniería Electrónica, Universidad Politécnica de Madrid, Ciudad Universitaria s/n, 28040 Madrid (Spain)
  2. Departamento de Ciencia de los Materiales e IM y QI, Universidad de Cádiz, 11510 Puerto Real (Cádiz) (Spain)
Publication Date:
OSTI Identifier:
22311217
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 105; Journal Issue: 4; Other Information: (c) 2014 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; ANTIMONY COMPOUNDS; CRYSTAL GROWTH; ELECTROLUMINESCENCE; ELECTRO-OPTICAL EFFECTS; FLUCTUATIONS; GALLIUM ARSENIDES; GROUND STATES; INDIUM ARSENIDES; INTERFACES; LAYERS; NITROGEN COMPOUNDS; PHOTOLUMINESCENCE; QUANTUM DOTS; QUANTUM EFFICIENCY; STRAINS; SUPERLATTICES; TEMPERATURE RANGE 0273-0400 K; TERNARY ALLOY SYSTEMS

Citation Formats

Utrilla, A. D., Ulloa, J. M., E-mail: jmulloa@isom.upm.es, Guzman, A., Hierro, A., Reyes, D. F., González, D., and Ben, T.. GaAsSb/GaAsN short-period superlattices as a capping layer for improved InAs quantum dot-based optoelectronics. United States: N. p., 2014. Web. doi:10.1063/1.4891557.
Utrilla, A. D., Ulloa, J. M., E-mail: jmulloa@isom.upm.es, Guzman, A., Hierro, A., Reyes, D. F., González, D., & Ben, T.. GaAsSb/GaAsN short-period superlattices as a capping layer for improved InAs quantum dot-based optoelectronics. United States. doi:10.1063/1.4891557.
Utrilla, A. D., Ulloa, J. M., E-mail: jmulloa@isom.upm.es, Guzman, A., Hierro, A., Reyes, D. F., González, D., and Ben, T.. Mon . "GaAsSb/GaAsN short-period superlattices as a capping layer for improved InAs quantum dot-based optoelectronics". United States. doi:10.1063/1.4891557.
@article{osti_22311217,
title = {GaAsSb/GaAsN short-period superlattices as a capping layer for improved InAs quantum dot-based optoelectronics},
author = {Utrilla, A. D. and Ulloa, J. M., E-mail: jmulloa@isom.upm.es and Guzman, A. and Hierro, A. and Reyes, D. F. and González, D. and Ben, T.},
abstractNote = {The application of a GaAsSb/GaAsN short-period superlattice capping layer (CL) on InAs/GaAs quantum dots (QDs) is shown to be an option for providing improved luminescence properties to this system. Separating both GaAsSb and GaAsN ternaries during the growth in 2 monolayer-thick phases solves the GaAsSbN immiscibility-related problems. Strong fluctuations in the CL composition and strain field as well as in the QD size distribution are significantly reduced, and a more regular CL interface is also obtained. Room-temperature (RT) photoluminescence (PL) is obtained for overall N contents as high as 3%, yielding PL peak wavelengths beyond 1.4 μm in samples with a type-II band alignment. High external quantum efficiency electroluminescence and photocurrent from the QD ground state are also demonstrated at RT in a single QD-layer p-i-n device. Thus, it becomes possible to combine and transfer the complementary benefits of Sb- and N-containing GaAs alloys to InAs QD-based optoelectronics.},
doi = {10.1063/1.4891557},
journal = {Applied Physics Letters},
number = 4,
volume = 105,
place = {United States},
year = {Mon Jul 28 00:00:00 EDT 2014},
month = {Mon Jul 28 00:00:00 EDT 2014}
}
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  • The MBE growth of short-period InAs/GaSb type-II superlattice structures, varied around 20.5 A InAs/24 A GaSb were [J. Applied physics, 96, 2580 (2004)] carried out by Haugan et al. These SLs were designed to produce devices with an optimum mid-infrared photoresponse and a sharpest photoresponse cutoff. We have used a realistic and reliable 14-band k.p formalism description of the superlattice electronic band structure to calculate the absorption coefficient in such short-period InAs/GaSb type-II superlattices. The parameters for this formalism are known from fitting to independent experiments for the bulk materials. The band-gap energies are obtained without any fitting parameters, andmore » are in good agreement with experimental data.« less