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

0371379 - FZÚ 2012 RIV NL eng J - Journal Article
Hospodková, Alice - Pangrác, Jiří - Oswald, Jiří - Hazdra, P. - Kuldová, Karla - Vyskočil, Jan - Hulicius, Eduard
Influence of strain reducing layers on electroluminescence and photoluminescence of InAs/GaAs QD structures.
Journal of Crystal Growth. Roč. 315, č. 1 (2011), 110-113. ISSN 0022-0248. E-ISSN 1873-5002
R&D Projects: GA ČR GAP102/10/1201; GA MŠMT LC510; GA ČR GA202/09/0676
Institutional research plan: CEZ:AV0Z10100521
Keywords : low dimensional structures * photoluminescence * electroluminescence * low-pressure MOVPE * InAs/GaAs quantum dots * semiconducting III–V materials
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 1.726, year: 2011

We present a comparison of photo- (PL) and electro-luminescence (EL) spectra of quantum dot (QD) structures with different strain reducing layers (SRL). Simple QD structures without SRL have negligible difference between the PL and EL maxima, which are near 1250 nm. InGaAs and GaAsSb SRLs were used to shift the luminescence maximum towards telecommunication wavelengths at 1.3 or 1.55 μm. We have found that MOVPE prepared QD structures with SRL exhibit an EL maximum at a considerably shorter wavelength than the PL maximum measured on similar samples without doping in the absence of built-in electric field. A mechanism to explain this phenomenon is proposed for both types of SRLs. The GaAsSb SRL is more suitable for long wavelength EL due to the higher confinement potential of electrons compared to InGaAs SRL. EL maximum at 1300 nm and PL maximum at 1520 nm were achieved on InAs QD structures with GaAs0.87Sb0.13 SRL (type I heterojunction).
Permanent Link: http://hdl.handle.net/11104/0204912