Please use this identifier to cite or link to this item:
logo share SHARE logo core CORE BASE
Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE

Enhancement of the photoluminescence intensity of a single InAs/GaAs quantum dot by separate generation of electrons and holes

AuthorsDonchev, V.; Moskalenko, E. S.; Karlsson, K. F.; Holtz, P. O.; Monemar, B.; Schoenfeld, W. V.; García Martínez, Jorge Manuel CSIC ORCID CVN ; Petroff, Pierre M.
Issue Date2006
CitationPhysics of the Solid State 48(10): 1993-1999 (2006)
AbstractIt is demonstrated that the microphotoluminescence (μPL) spectrum of a single InAs/GaAs self-assembled quantum dot (QD) undergoes considerable changes when the primary laser excitation is complemented with an additional infrared laser. The primary laser, tuned slightly below the GaAs band gap, provides electron-hole pairs in the wetting layer (WL), as well as excess free electrons from ionized shallow acceptors in the GaAs barriers. An additional IR laser with a fixed energy well below the QD ground state transition generates excess free holes from deep levels in GaAs. The excess electron and hole will experience diffusion separately, due to the time separation between the two events of their generation, to eventually become captured into the QD. Although the generation rates of excess carries are much lower than that of the electron-hole pair generation in the WL, they considerably influence the QD emission at low temperatures. The integrated PL intensity increases by several times as compared to single-laser excitation, and the QD exciton spectrum is redistributed in favor of a more neutral charge configuration. The dependence of the observed phenomenon on the powers of the two lasers and the temperature has been studied and is consistent with the model proposed. The concept of dual excitation could be successfully applied to different low-dimensional semiconductor structures in order to manipulate their charge state and emission intensity.
Description7 páginas, 5 figuras.-- PACS numbers: 78.67.Hc, 71.55.Eq, 73.50.Gr
Publisher version (URL)
Appears in Collections:(IMN-CNM) Artículos

Files in This Item:
File Description SizeFormat
p1877-1882.pdf282,57 kBAdobe PDFThumbnail
Show full item record
Review this work

Page view(s)

checked on May 16, 2022


checked on May 16, 2022

Google ScholarTM




WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.