InGaAs and GaAsSb strain reducing layers covering InAs/GaAs quantum dots

0342440 - FZÚ 2011 RIV NL eng J - Journal Article
Hospodková, Alice - Hulicius, Eduard - Pangrác, Jiří - Oswald, Jiří - Vyskočil, Jan - Kuldová, Karla - Šimeček, Tomislav - Hazdra, P. - Caha, O.
InGaAs and GaAsSb strain reducing layers covering InAs/GaAs quantum dots.
Journal of Crystal Growth. Roč. 312, č. 8 (2010), 1383-1387. ISSN 0022-0248. E-ISSN 1873-5002
R&D Projects: GA AV ČR IAA100100719; GA ČR GA202/09/0676; GA MŠMT LC510
Institutional research plan: CEZ:AV0Z10100521
Keywords : low dimensional structures * photoluminescence * low-pressure MOVPE * InAs/GaAs quantum dots * semiconducting III/V materials
Subject RIV: BM - Solid Matter Physics ; Magnetism
Impact factor: 1.737, year: 2010

We compare properties of InAs/GaAs quantum dots(QDs)covered by InGaAs or GaAsSb strain reducing layers (SRLs)prepared by metalorganic vapor phase epitaxy.Stronger redshift of QD emission was achieved with InGaAs SRL as compared to GaAsSb one with similar strain in the structure. This can be caused by the increase of QD size during InGaAs SRL growth. The heterojunction between InAsQDs and GaAsSb SRL changes from type I totype II between 13% and 15%of Sb in the SRL. Important advantage of GaAsSb SRL can be the possibility to change the overlap of electron and hole wave functions and QD dipole moment orientation by the composition of GaAsSb. We have achieved the highest PL intensity suggesting best wave function overlap near 13%of Sb in the SRL. Band alignment, transition probability and transition energy were calculated to help the interpretation of achieved results.
Permanent Link: http://hdl.handle.net/11104/0185175