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Excited States and Their Dynamics in CdSe Quantum Dots Studied by Two-Color 2D Spectroscopy
[Image: see text] Quantum dots (QDs) form a promising family of nanomaterials for various applications in optoelectronics. Understanding the details of the excited-state dynamics in QDs is vital for optimizing their function. We apply two-color 2D electronic spectroscopy to investigate CdSe QDs at 7...
Autores principales: | , , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
American Chemical Society
2022
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8842281/ https://www.ncbi.nlm.nih.gov/pubmed/35089715 http://dx.doi.org/10.1021/acs.jpclett.1c04110 |
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author | Wang, Zhengjun Lenngren, Nils Amarotti, Edoardo Hedse, Albin Žídek, Karel Zheng, Kaibo Zigmantas, Donatas Pullerits, Tõnu |
author_facet | Wang, Zhengjun Lenngren, Nils Amarotti, Edoardo Hedse, Albin Žídek, Karel Zheng, Kaibo Zigmantas, Donatas Pullerits, Tõnu |
author_sort | Wang, Zhengjun |
collection | PubMed |
description | [Image: see text] Quantum dots (QDs) form a promising family of nanomaterials for various applications in optoelectronics. Understanding the details of the excited-state dynamics in QDs is vital for optimizing their function. We apply two-color 2D electronic spectroscopy to investigate CdSe QDs at 77 K within a broad spectral range. Analysis of the electronic dynamics during the population time allows us to identify the details of the excitation pathways. The initially excited high-energy electrons relax with the time constant of 100 fs. Simultaneously, the states at the band edge rise within 700 fs. Remarkably, the excited-state absorption is rising with a very similar time constant of 700 fs. This makes us reconsider the earlier interpretation of the excited-state absorption as the signature of a long-lived trap state. Instead, we propose that this signal originates from the excitation of the electrons that have arrived in the conduction-band edge. |
format | Online Article Text |
id | pubmed-8842281 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2022 |
publisher | American Chemical Society |
record_format | MEDLINE/PubMed |
spelling | pubmed-88422812022-02-15 Excited States and Their Dynamics in CdSe Quantum Dots Studied by Two-Color 2D Spectroscopy Wang, Zhengjun Lenngren, Nils Amarotti, Edoardo Hedse, Albin Žídek, Karel Zheng, Kaibo Zigmantas, Donatas Pullerits, Tõnu J Phys Chem Lett [Image: see text] Quantum dots (QDs) form a promising family of nanomaterials for various applications in optoelectronics. Understanding the details of the excited-state dynamics in QDs is vital for optimizing their function. We apply two-color 2D electronic spectroscopy to investigate CdSe QDs at 77 K within a broad spectral range. Analysis of the electronic dynamics during the population time allows us to identify the details of the excitation pathways. The initially excited high-energy electrons relax with the time constant of 100 fs. Simultaneously, the states at the band edge rise within 700 fs. Remarkably, the excited-state absorption is rising with a very similar time constant of 700 fs. This makes us reconsider the earlier interpretation of the excited-state absorption as the signature of a long-lived trap state. Instead, we propose that this signal originates from the excitation of the electrons that have arrived in the conduction-band edge. American Chemical Society 2022-01-28 2022-02-10 /pmc/articles/PMC8842281/ /pubmed/35089715 http://dx.doi.org/10.1021/acs.jpclett.1c04110 Text en © 2022 The Authors. Published by American Chemical Society https://creativecommons.org/licenses/by/4.0/Permits the broadest form of re-use including for commercial purposes, provided that author attribution and integrity are maintained (https://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Wang, Zhengjun Lenngren, Nils Amarotti, Edoardo Hedse, Albin Žídek, Karel Zheng, Kaibo Zigmantas, Donatas Pullerits, Tõnu Excited States and Their Dynamics in CdSe Quantum Dots Studied by Two-Color 2D Spectroscopy |
title | Excited States and Their Dynamics in CdSe Quantum
Dots Studied by Two-Color 2D Spectroscopy |
title_full | Excited States and Their Dynamics in CdSe Quantum
Dots Studied by Two-Color 2D Spectroscopy |
title_fullStr | Excited States and Their Dynamics in CdSe Quantum
Dots Studied by Two-Color 2D Spectroscopy |
title_full_unstemmed | Excited States and Their Dynamics in CdSe Quantum
Dots Studied by Two-Color 2D Spectroscopy |
title_short | Excited States and Their Dynamics in CdSe Quantum
Dots Studied by Two-Color 2D Spectroscopy |
title_sort | excited states and their dynamics in cdse quantum
dots studied by two-color 2d spectroscopy |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8842281/ https://www.ncbi.nlm.nih.gov/pubmed/35089715 http://dx.doi.org/10.1021/acs.jpclett.1c04110 |
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