Influence of strain reducing layer type on electroluminescence and photoluminescence of InAs/GaAs QD structures

0373106 - FZÚ 2012 US eng A - Abstract
Hospodková, Alice - Pangrác, Jiří - Oswald, Jiří - Hazdra, P. - Kuldová, Karla - Vyskočil, Jan - Hulicius, Eduard - Šimeček, Tomislav
Influence of strain reducing layer type on electroluminescence and photoluminescence of InAs/GaAs QD structures.
IC-MOVPE XV. Warrendale: TMS, 2010. s. 44.
[International Metal Organic Vapor Phase Epitaxy Conference /15./. 23.05.2010-28.05.2010, Hyatt Regency Lake Tahoe]
R&D Projects: GA ČR GAP102/10/1201; GA ČR GA202/09/0676
Institutional research plan: CEZ:AV0Z10100521
Keywords : InAs/GaAs * quantum dots * MOVPE
Subject RIV: BM - Solid Matter Physics ; Magnetism

We present a comparison of photo- (PL) and electroluminescence (EL) spectra of quantum dot (QD) structures with different strain reducing layer (SRL). Simple QD structures without SRL have negligible shift between PL and EL maxima, at 1240 nm. InGaAs and GaAsSb strain reducing layers (SRL) were used to shift the luminescence maximum towards telecommunication wavelengths at 1.3 or 1.55 µm. We show that MOVPE prepared QDs with SRL exhibit considerable blue shift of EL maximum or lasing wavelength in comparison to their PL maximum measured in the absence of electric field. The mechanism of this blue shift is proposed for both types of SRLs. The GaAsSb SRL is more suitable for long wavelength EL due to higher confinement potential for electrons compared to InGaAs SRL. EL maximum at 1300 nm and PL maximum at 1520 nm were achieved on InAs QDs with GaAs0.87Sb0.13 SRL (type I heterojunction).
Permanent Link: http://hdl.handle.net/11104/0206262