Recombination properties of Si-doped InGaAs/GaAs quantum dots
2006 (English)In: Nanotechnology, ISSN 0957-4484, E-ISSN 1361-6528, Vol. 17, no 21, 5373-5377 p.Article in journal (Refereed) Published
The recombination properties of directly doped InGaAs/GaAs quantum dots (QDs) for application in quantum dot infrared photodetectors (QDIPs) have been investigated by time-resolved photoluminescence. Compared with undoped and barrier-doped samples, the overall effect of direct dot doping is found to be small, resulting in only slight deterioration of dot homogeneity. Low-temperature photoluminescence decay times decrease very little, indicating that direct doping does not cause a significant increase of nonradiative recombination. In addition, directly doped quantum dots show a significantly weaker quenching of the photoluminescence intensity with temperature. At the same time, barrier doping causes the formation of more and smaller dots, which results in high photoluminescence intensity at low temperatures but an early onset of thermal carrier emission from the dots. The results suggest that direct QD doping is more prospective for realizing room-temperature operation in QDIPs.
Place, publisher, year, edition, pages
2006. Vol. 17, no 21, 5373-5377 p.
infrared photodetectors, room-temperature, inas, gaas, photoluminescence, responsivity, growth, lasers
Atom and Molecular Physics and Optics
IdentifiersURN: urn:nbn:se:kth:diva-5881DOI: 10.1088/0957-4484/17/21/015ISI: 000241856200015ScopusID: 2-s2.0-33846117095OAI: oai:DiVA.org:kth-5881DiVA: diva2:10408
Uppdaterad från submitted till published: 20100920
QC 201009202006-06-012006-06-012010-09-20Bibliographically approved