English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/29050
Share/Impact:
Statistics
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL
Exportar a otros formatos:

Title

Effect of an additional infrared excitation on the luminescence efficiency of a single InAs/GaAs quantum dot

AuthorsMoskalenko, E. S.; Donchev, V.; Karlsson, K. F.; Holtz, P. O.; Monemar, B.; Schoenfeld, W. V.; García Martínez, Jorge Manuel ; Petroff, Pierre M.
Issue Date20-Oct-2003
PublisherAmerican Physical Society
CitationPhysical Review B 68(15): 155317 (2003)
AbstractMicrophotoluminescence (PL) spectra of a single InAs/GaAs self-assembled quantum dot (QD) are studied under the main excitation of electron-hole pairs in the wetting layer (WL) and an additional infrared (IR) laser illumination. It is demonstrated that the IR laser with fixed photon energy well below the QD ground state induces striking changes in the spectra for a range of excitation energies and powers of the two lasers. For the main excitation above a threshold energy, defined as the onset of transitions between shallow acceptors and the conduction band in GaAs, the addition of the IR laser will induce a considerable increase in the QD emission intensity. This is explained in terms of additional generation of extra electrons and holes into the QD by the two lasers. For excitation below the threshold energy, the carrier capture efficiency from the WL into the QD is suggested to be essentially determined by the internal electric-field-driven carrier transport in the plane of the WL. The extra holes, generated in the GaAs by the IR laser, are supposed to effectively screen the built-in field, which results in a considerable reduction of the carrier collection efficiency into the QD and, consequently, a decrease of the QD PL intensity. A model is presented which allows estimating the magnitude of the built-in field as well as the dependence of the observed increase of the QD PL intensity on the powers of the two lasers. The use of an additional IR laser is considered to be helpful to effectively manipulate the emission efficiency of the quantum dot, which could be used in practice in quantum-dot-based optical switches.
Description14 páginas, 7 figuras.-- PACS number(s): 78.67.Hc, 71.55.Eq, 78.66.Fd
Publisher version (URL)http://link.aps.org/doi/10.1103/PhysRevB.68.155317
URIhttp://hdl.handle.net/10261/29050
DOI10.1103/PhysRevB.68.155317
ISSN1098-0121
Appears in Collections:(IMN-CNM) Artículos
Files in This Item:
File Description SizeFormat 
e155317.pdf183,65 kBAdobe PDFThumbnail
View/Open
Show full item record
Review this work
 

Related articles:


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