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Title: Compressive and Tensile Stress in CdSe Semiconductor Quantum Dots

Abstract

Compressive and tensile stress in colloidal CdSe quantum dots (QDs) is examined using resonance Raman spectroscopy. We find that the dispersion of the longitudinal optical phonon mode with size does not follow theoretical calculations based on phonon confinement models. To account for these deviations, the presence of compressive or tensile stress in the QDs was proposed. We find that CdSe QDs prepared via a single source precursor (SSP) method exhibit compressive stress, while CdSe QDs prepared via high temperature lyothermal methods exhibit tensile stress. Evidence is provided that the SSP CdSe QDs stress is directly related to a surface effect.

Authors:
; ;
Publication Date:
Research Org.:
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
15011574
Report Number(s):
UCRL-JRNL-204519
TRN: US200507%%557
DOE Contract Number:
W-7405-ENG-48
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review B; Journal Volume: 70
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; CONFINEMENT; PHONONS; PRECURSOR; QUANTUM DOTS; RAMAN SPECTROSCOPY; RESONANCE

Citation Formats

Meulenberg, R W, Jennings, T, and Strouse, G F. Compressive and Tensile Stress in CdSe Semiconductor Quantum Dots. United States: N. p., 2004. Web. doi:10.1103/PhysRevB.70.235311.
Meulenberg, R W, Jennings, T, & Strouse, G F. Compressive and Tensile Stress in CdSe Semiconductor Quantum Dots. United States. doi:10.1103/PhysRevB.70.235311.
Meulenberg, R W, Jennings, T, and Strouse, G F. 2004. "Compressive and Tensile Stress in CdSe Semiconductor Quantum Dots". United States. doi:10.1103/PhysRevB.70.235311. https://www.osti.gov/servlets/purl/15011574.
@article{osti_15011574,
title = {Compressive and Tensile Stress in CdSe Semiconductor Quantum Dots},
author = {Meulenberg, R W and Jennings, T and Strouse, G F},
abstractNote = {Compressive and tensile stress in colloidal CdSe quantum dots (QDs) is examined using resonance Raman spectroscopy. We find that the dispersion of the longitudinal optical phonon mode with size does not follow theoretical calculations based on phonon confinement models. To account for these deviations, the presence of compressive or tensile stress in the QDs was proposed. We find that CdSe QDs prepared via a single source precursor (SSP) method exhibit compressive stress, while CdSe QDs prepared via high temperature lyothermal methods exhibit tensile stress. Evidence is provided that the SSP CdSe QDs stress is directly related to a surface effect.},
doi = {10.1103/PhysRevB.70.235311},
journal = {Physical Review B},
number = ,
volume = 70,
place = {United States},
year = 2004,
month = 6
}
  • No abstract prepared.
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