| Texto completo | |
| Autor(es): |
Gordo, Vanessa Orsi
[1]
;
Rodrigues, Leonarde N.
[2, 3]
;
Knopper, Floris
[3, 4]
;
Garcia Jr, Ailton J.
;
Iikawa, Fernando
[5]
;
Couto Jr, Odilon D. D.
;
Deneke, Christoph
[6]
Número total de Autores: 7
|
| Afiliação do(s) autor(es): | [1] Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083859 Campinas, SP - Brazil
[2] Univ Fed Vicosa, Dept Fis, BR-36570000 Vicosa, MG - Brazil
[3] Lab Nacl Nanotecnol LNNano CNPEM, BR-13083100 Campinas - Brazil
[4] Eindhoven Univ Technol TUe, Dept Appl Phys, Photon & Semicond Nanophys, POB 513, NL-5600 MB Eindhoven - Netherlands
[5] Garcia Jr, Jr., Ailton J., Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083859 Campinas, SP - Brazil
[6] Couto Jr, Jr., Odilon D. D., Garcia Jr, Jr., Ailton J., Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083859 Campinas, SP - Brazil
Número total de Afiliações: 6
|
| Tipo de documento: | Artigo Científico |
| Fonte: | Nanotechnology; v. 31, n. 25 APR 3 2020. |
| Citações Web of Science: | 0 |
| Resumo | |
We investigate the optical properties of strain-free mesoscopic GaAs/AlxGa1 - xAs structures (MGS) coupled to thin GaAs/AlxGa1 - xAs quantum wells (QWs) with varying Al content (x). We demonstrate that quenching the QW emission by controlling the band crossover between AlGaAs (X-point) and GaAs (Gamma-point) gives rise to long carrier lifetimes and enhanced optical emission from the MGS. For x = 0.33, QW and MGS show typical type-I band alignment with strong QW photoluminescence emission and much weaker sharp recombination lines from the MGS localized exciton states. For x >= 0.50, the QW emission is considerably quenched due to the change from type-I to type-II structure while the MGS emission is enhanced due to carrier injection from the QW. For x >= 0.70, we observe PL quenching from the MGS higher energy states also due to the crossover of X and Gamma bands, demonstrating spectral filtering of the MGS emission. Time-resolved measurements reveal two recombination processes in the MGS emission dynamics. The fast component depends mainly on the X - Gamma mixing of the MGS states and can be increased from 0.3 to 2.5 ns by changing the Al content. The slower component, however, depends on the X - Gamma mixing of the QW states and is associated to the carrier injection rate from the QW reservoir into the MGS structure. In this way, the independent tuning of X - Gamma mixing in QW and MGS states allows us to manipulate recombination rates in the MGS as well as to make carrier injection and light extraction more efficient. (AU) | |
| Processo FAPESP: | 16/16365-6 - Nanoestruturas de semicondutoras III-V e suas propriedades ópticas |
| Beneficiário: | Fernando Iikawa |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 16/14001-7 - Crescimento e fabricação de estruturas de membranas semicondutores para a pesquisa básica e aplicações de dispositivos potenciais |
| Beneficiário: | Christoph Friedrich Deneke |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 12/11382-9 - Modulação ótica de sistemas nanoestruturados usando ondas acústicas de superfícies |
| Beneficiário: | Odilon Divino Damasceno Couto Júnior |
| Modalidade de apoio: | Auxílio à Pesquisa - Jovens Pesquisadores |