States of direct and indirect excitons in strained zinc-blende GaN/InGaN asymmetric quantum wells
Autor: | M.E. Mora-Ramos, J.C. Martínez-Orozco, J.G. Rojas-Briseño |
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Rok vydání: | 2017 |
Předmět: |
Photoluminescence
Exciton media_common.quotation_subject Binding energy chemistry.chemical_element 02 engineering and technology 01 natural sciences Asymmetry Condensed Matter::Materials Science 0103 physical sciences General Materials Science Electrical and Electronic Engineering Biexciton Quantum well media_common 010302 applied physics Physics Condensed matter physics Condensed Matter::Other Heterojunction Condensed Matter::Mesoscopic Systems and Quantum Hall Effect 021001 nanoscience & nanotechnology Condensed Matter Physics chemistry 0210 nano-technology Indium |
Zdroj: | Superlattices and Microstructures. 112:574-583 |
ISSN: | 0749-6036 |
DOI: | 10.1016/j.spmi.2017.10.017 |
Popis: | The total and binding energies of excitons in step-like asymmetric quantum wells made of zincblende GaN/InxlGa(1−xl)N/InxrGa(1−xr)N/GaN are theoretically reported. It is discussed how the asymmetry in the carrier confinement leads to singular behaviors in the exciton binding energy, allowing to observe both direct and indirect exciton states in the heterostructure. The study is carried out with the use of the effective mass approximation. The effects of strain are taken into account and a comparison of the results obtained for both strained and unstrained situations is presented. Exciton energy shows a decreasing behavior when the size of the effective confinement region is augmented. The total exciton energy as well as the binding energy are reported as functions of the indium concentration and quantum well width. In addition, the results of the calculation of the photoluminescence peak are presented. For this latter quantity, our results for the limiting case of a single zinc-blende GaN/InGaN quantum well show very good agreement with published experimental ones. |
Databáze: | OpenAIRE |
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