| Autor: |
Tian, Ming, Ma, Cangmin, Lin, Tao, Liu, Jianping, Talwar, Devki N., Yang, Hui, Cao, Jiehua, Huang, Xinying, Niu, Wenlong, Ferguson, Ian T., Wan, Lingyu, Feng, Zhe Chuan |
| Předmět: |
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| Zdroj: |
Journal of Materials Science; Jan2021, Vol. 56 Issue 2, p1481-1491, 11p, 1 Color Photograph, 6 Graphs |
| Abstrakt: |
Exciton localization phenomena are considered here to comprehend the high internal quantum efficiency in InGaN/GaN multiple-quantum-well structures having discrete quantum dots (QDs) prepared by metal–organic-chemical-vapor deposition method on c-sapphire substrates. Spectroscopic results from the variable-temperature steady-state-photoluminescence and time-resolved photoluminescence (TRPL) are investigated. While the exciton localization is enhanced by strong localized states within the InGaN/GaN QDs–the impact of free carrier recombination cannot be ignored. The observed non-exponential decay in TRPL measurements is explained using a model by meticulously including localized exciton, non-radiative and free carrier recombination rates. A new method is proposed to calculate the internal quantum efficiency, which is supplementary to the traditional approach based on temperature-dependent photoluminescence measurement. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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