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Title: Electron and Hole Addition Energies in PbSe Quantum Dots

Abstract

We calculate electron and hole addition energies of PbSe quantum dots using a pseudopotential configuration-interaction approach. We find that (i) the addition energies are nearly constant for the first eight carriers occupying the S-like shell. (ii) The charging sequence of the first eight carriers is non-Aufbau, but filling of the P-like single-particle states takes place only after the S-like states are filled. (iii) The charging spectrum shows bunching-up of all lines as the dielectric constant {var_epsilon}{sub out} of the material surrounding the dot increases. At the same time, the addition energies are significantly reduced. (iv) The calculated optical gap shows a rather weak dependence on {var_epsilon}{sub out}, reflecting a cancellation between electron-hole interaction energies and surface polarization self-energies.

Authors:
; ;
Publication Date:
Research Org.:
National Renewable Energy Lab. (NREL), Golden, CO (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
981985
DOE Contract Number:
AC36-08GO28308
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. B, Condensed Matter and Materials Physics; Journal Volume: 76; Journal Issue: 4, 2007; Related Information: Article no. 045401
Country of Publication:
United States
Language:
English
Subject:
77 NANOSCIENCE AND NANOTECHNOLOGY; CANCELLATION; CARRIERS; CONFIGURATION INTERACTION; ELECTRONS; HOLES; INTERACTIONS; MATERIALS; PERMITTIVITY; POLARIZATION; QUANTUM DOTS; SURFACES; Basic Sciences; Solid State Theory

Citation Formats

An, J. M., Franceschetti, A., and Zunger, A. Electron and Hole Addition Energies in PbSe Quantum Dots. United States: N. p., 2007. Web. doi:10.1103/PhysRevB.76.045401.
An, J. M., Franceschetti, A., & Zunger, A. Electron and Hole Addition Energies in PbSe Quantum Dots. United States. doi:10.1103/PhysRevB.76.045401.
An, J. M., Franceschetti, A., and Zunger, A. Mon . "Electron and Hole Addition Energies in PbSe Quantum Dots". United States. doi:10.1103/PhysRevB.76.045401.
@article{osti_981985,
title = {Electron and Hole Addition Energies in PbSe Quantum Dots},
author = {An, J. M. and Franceschetti, A. and Zunger, A.},
abstractNote = {We calculate electron and hole addition energies of PbSe quantum dots using a pseudopotential configuration-interaction approach. We find that (i) the addition energies are nearly constant for the first eight carriers occupying the S-like shell. (ii) The charging sequence of the first eight carriers is non-Aufbau, but filling of the P-like single-particle states takes place only after the S-like states are filled. (iii) The charging spectrum shows bunching-up of all lines as the dielectric constant {var_epsilon}{sub out} of the material surrounding the dot increases. At the same time, the addition energies are significantly reduced. (iv) The calculated optical gap shows a rather weak dependence on {var_epsilon}{sub out}, reflecting a cancellation between electron-hole interaction energies and surface polarization self-energies.},
doi = {10.1103/PhysRevB.76.045401},
journal = {Physical Review. B, Condensed Matter and Materials Physics},
number = 4, 2007,
volume = 76,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
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