Detection of optical emissions from deep localized states in a self-assembled InAs/GaAs QD structure
This work reports on the optical properties of self-assembled InAs/GaAs quantum dots (QDs) grown by molecular beam epitaxy. A sigmoidal temperature-dependent variation of the bandgap energy of the dots is detected from the photoluminescence (PL) investigations of the studied sample. This sigmoidal d...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Elsevier
2022-02-01
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| Series: | Applied Surface Science Advances |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S2666523921001458 |
| _version_ | 1818969042194530304 |
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| author | Rihani Jawher Mehrez Oueslati Vincent Sallet Jean-Christophe Harmand Radhwen Chtourou |
| author_facet | Rihani Jawher Mehrez Oueslati Vincent Sallet Jean-Christophe Harmand Radhwen Chtourou |
| author_sort | Rihani Jawher |
| collection | DOAJ |
| description | This work reports on the optical properties of self-assembled InAs/GaAs quantum dots (QDs) grown by molecular beam epitaxy. A sigmoidal temperature-dependent variation of the bandgap energy of the dots is detected from the photoluminescence (PL) investigations of the studied sample. This sigmoidal dependence of the bandgap energy was accompanied by an anomalous increase in the integrated PL intensity (IPLI) over the temperature range of 10 K to 110 K. Such optical observations are related to the existence of deep localized states (LS) within the QD structure. To illustrate the presence of the LS, pump power-dependent PL measurements at different temperatures were performed. It is found that the sigmoidal dependence of the PL peak energy (PLPE) gradually converts into a monotonous variation with the gradual increase in the excitation density. These observations show a saturation behavior of a limited number of states within the bandgap of the QDs. Such optical results provide clear evidence for the existence of deep levels within the InAs dots. |
| first_indexed | 2024-12-20T14:14:17Z |
| format | Article |
| id | doaj.art-59e259f6c7e646859f9a5ea06b696b6d |
| institution | Directory Open Access Journal |
| issn | 2666-5239 |
| language | English |
| last_indexed | 2024-12-20T14:14:17Z |
| publishDate | 2022-02-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Applied Surface Science Advances |
| spelling | doaj.art-59e259f6c7e646859f9a5ea06b696b6d2022-12-21T19:38:05ZengElsevierApplied Surface Science Advances2666-52392022-02-017100199Detection of optical emissions from deep localized states in a self-assembled InAs/GaAs QD structureRihani Jawher0Mehrez Oueslati1Vincent Sallet2Jean-Christophe Harmand3Radhwen Chtourou4Laboratoire de Photovoltaïque de Semiconducteurs et de Nanostructures, Centre de Recherche des Sciences et Technologie de l'Energie, BP. 95, Hammam-Lif 2050, Tunisia; Corresponding author at: Laboratoire de Physique et des Semiconducteurs, centre de Recherche et de Technologie de l'Energie, Hammam Lif, Borj Cedria 2050, Tunisia.Laboratoire de Nanomatériaux, Nanotechnologie et Energie (L2NE), Faculté des Sciences de Tunis, Université de Tunis El Manar, 2092 Tunis, TunisiaGroupe d'Etude de la Matière Condensée (GEMAC), CNRS, Université St Quentin en Yvelines, Université Paris-Saclay, 45 avenue des Etats-Unis, 78035 Versailles, FranceCentre de Nanosciences et de Nanotechnologies (C2T), Université Paris-Saclay, UMR 9001 CNRS, 10 Boulevard Thomas, Gobert, 91120 Palaiseau, FranceLaboratoire de Photovoltaïque de Semiconducteurs et de Nanostructures, Centre de Recherche des Sciences et Technologie de l'Energie, BP. 95, Hammam-Lif 2050, TunisiaThis work reports on the optical properties of self-assembled InAs/GaAs quantum dots (QDs) grown by molecular beam epitaxy. A sigmoidal temperature-dependent variation of the bandgap energy of the dots is detected from the photoluminescence (PL) investigations of the studied sample. This sigmoidal dependence of the bandgap energy was accompanied by an anomalous increase in the integrated PL intensity (IPLI) over the temperature range of 10 K to 110 K. Such optical observations are related to the existence of deep localized states (LS) within the QD structure. To illustrate the presence of the LS, pump power-dependent PL measurements at different temperatures were performed. It is found that the sigmoidal dependence of the PL peak energy (PLPE) gradually converts into a monotonous variation with the gradual increase in the excitation density. These observations show a saturation behavior of a limited number of states within the bandgap of the QDs. Such optical results provide clear evidence for the existence of deep levels within the InAs dots.http://www.sciencedirect.com/science/article/pii/S2666523921001458Quantum DotsDeep localized statesCarrier exchange in the QD structuresPhotoluminescence spectroscopyTemperature-dependent PL measurementsPump power-dependent PL investigations |
| spellingShingle | Rihani Jawher Mehrez Oueslati Vincent Sallet Jean-Christophe Harmand Radhwen Chtourou Detection of optical emissions from deep localized states in a self-assembled InAs/GaAs QD structure Applied Surface Science Advances Quantum Dots Deep localized states Carrier exchange in the QD structures Photoluminescence spectroscopy Temperature-dependent PL measurements Pump power-dependent PL investigations |
| title | Detection of optical emissions from deep localized states in a self-assembled InAs/GaAs QD structure |
| title_full | Detection of optical emissions from deep localized states in a self-assembled InAs/GaAs QD structure |
| title_fullStr | Detection of optical emissions from deep localized states in a self-assembled InAs/GaAs QD structure |
| title_full_unstemmed | Detection of optical emissions from deep localized states in a self-assembled InAs/GaAs QD structure |
| title_short | Detection of optical emissions from deep localized states in a self-assembled InAs/GaAs QD structure |
| title_sort | detection of optical emissions from deep localized states in a self assembled inas gaas qd structure |
| topic | Quantum Dots Deep localized states Carrier exchange in the QD structures Photoluminescence spectroscopy Temperature-dependent PL measurements Pump power-dependent PL investigations |
| url | http://www.sciencedirect.com/science/article/pii/S2666523921001458 |
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