Biexciton Dynamics in Single Colloidal CdSe Quantum Dots
| Autor: | Ruiyun Chen, Jie Ma, Changgang Yang, Wenli Guo, Yujun Zheng, Jianyong Hu, Yan Gao, Suotang Jia, Guofeng Zhang, Haizheng Zhong, Yong-Gang Peng, Bin Li, Chengbing Qin, Yong Zhang, Ruixiang Wu, Liantuan Xiao |
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| Rok vydání: | 2020 |
| Předmět: |
Materials science
Photoluminescence Auger effect Quantum yield 02 engineering and technology 021001 nanoscience & nanotechnology 01 natural sciences Molecular physics symbols.namesake Colloid Quantum dot 0103 physical sciences Radiative transfer symbols General Materials Science Physical and Theoretical Chemistry 010306 general physics 0210 nano-technology Recombination Biexciton |
| Zdroj: | The journal of physical chemistry letters. 11(24) |
| ISSN: | 1948-7185 |
| Popis: | The investigation of biexciton dynamics in single colloidal quantum dots (QDs) is critical to biexciton-based applications. Generally, a biexciton exhibits an extremely low photoluminescence (PL) quantum yield as well as very fast PL decay due to strong nonradiative Auger recombination, making it difficult to investigate the biexciton dynamics. Here, we develop a quantitative method based on intensity- and time-resolved photon statistics to investigate the biexciton dynamics in single colloidal QDs. This robust method can be used under high-excitation conditions to determine the absolute radiative and Auger recombination rates of both neutral and charged biexciton states in a single QD level, and the corresponding ratios between the two states agree with the theoretical predictions of the asymmetric band structures of CdSe-based QDs. Furthermore, the surface traps are found to provide additional nonradiative recombination pathways for the biexcitons, and their contributions are quantified by the method. |
| Databáze: | OpenAIRE |
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