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Title: Effect of spacer layer thickness on structural and optical properties of multi-stack InAs/GaAsSb quantum dots

Abstract

The structural and optical properties of ten-stack InAs/GaAsSb quantum dots (QDs) with different spacer layer thicknesses (d{sub s} = 2, 5, 10, and 15 nm) are reported. X-ray diffraction analysis reveals that the strain relaxation of the GaAsSb spacers increases linearly from 0% to 67% with larger d{sub s} due to higher elastic stress between the spacer and GaAs matrix. In addition, the dislocation density in the spacers with d{sub s} = 10 nm is lowest as a result of reduced residual strain. The photoluminescence peak energy from the QDs does not change monotonically with increasing d{sub s} due to the competing effects of decreased compressive strain and weak electronic coupling of stacked QD layers. The QD structure with d{sub s} = 10 nm is demonstrated to have improved luminescence properties and higher carrier thermal stability.

Authors:
; ;  [1]; ;  [2]
  1. School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85287 (United States)
  2. Department of Physics, Arizona State University, Tempe, Arizona 85287 (United States)
Publication Date:
OSTI Identifier:
22485975
Resource Type:
Journal Article
Resource Relation:
Journal Name: Applied Physics Letters; Journal Volume: 107; Journal Issue: 17; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CARRIERS; DISLOCATIONS; GALLIUM ARSENIDES; INDIUM ARSENIDES; LAYERS; OPTICAL PROPERTIES; PHOTOLUMINESCENCE; QUANTUM DOTS; STRAINS; STRESSES; THICKNESS; X-RAY DIFFRACTION

Citation Formats

Kim, Yeongho, Ban, Keun-Yong, E-mail: kban1@asu.edu, Honsberg, Christiana B., Boley, Allison, and Smith, David J. Effect of spacer layer thickness on structural and optical properties of multi-stack InAs/GaAsSb quantum dots. United States: N. p., 2015. Web. doi:10.1063/1.4934695.
Kim, Yeongho, Ban, Keun-Yong, E-mail: kban1@asu.edu, Honsberg, Christiana B., Boley, Allison, & Smith, David J. Effect of spacer layer thickness on structural and optical properties of multi-stack InAs/GaAsSb quantum dots. United States. doi:10.1063/1.4934695.
Kim, Yeongho, Ban, Keun-Yong, E-mail: kban1@asu.edu, Honsberg, Christiana B., Boley, Allison, and Smith, David J. 2015. "Effect of spacer layer thickness on structural and optical properties of multi-stack InAs/GaAsSb quantum dots". United States. doi:10.1063/1.4934695.
@article{osti_22485975,
title = {Effect of spacer layer thickness on structural and optical properties of multi-stack InAs/GaAsSb quantum dots},
author = {Kim, Yeongho and Ban, Keun-Yong, E-mail: kban1@asu.edu and Honsberg, Christiana B. and Boley, Allison and Smith, David J.},
abstractNote = {The structural and optical properties of ten-stack InAs/GaAsSb quantum dots (QDs) with different spacer layer thicknesses (d{sub s} = 2, 5, 10, and 15 nm) are reported. X-ray diffraction analysis reveals that the strain relaxation of the GaAsSb spacers increases linearly from 0% to 67% with larger d{sub s} due to higher elastic stress between the spacer and GaAs matrix. In addition, the dislocation density in the spacers with d{sub s} = 10 nm is lowest as a result of reduced residual strain. The photoluminescence peak energy from the QDs does not change monotonically with increasing d{sub s} due to the competing effects of decreased compressive strain and weak electronic coupling of stacked QD layers. The QD structure with d{sub s} = 10 nm is demonstrated to have improved luminescence properties and higher carrier thermal stability.},
doi = {10.1063/1.4934695},
journal = {Applied Physics Letters},
number = 17,
volume = 107,
place = {United States},
year = 2015,
month =
}
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