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Polarons Explain Luminescence Behavior of Colloidal Quantum Dots at Low Temperature
Luminescence properties of colloidal quantum dots have found applications in imaging, displays, light-emitting diodes and lasers, and single photon sources. Despite wide interest, several experimental observations in low-temperature photoluminescence of these quantum dots, such as the short lifetime...
Autores principales: | , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Nature Publishing Group UK
2018
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5976793/ https://www.ncbi.nlm.nih.gov/pubmed/29849075 http://dx.doi.org/10.1038/s41598-018-26678-w |
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author | Khosla, Meenakshi Rao, Sravya Gupta, Shilpi |
author_facet | Khosla, Meenakshi Rao, Sravya Gupta, Shilpi |
author_sort | Khosla, Meenakshi |
collection | PubMed |
description | Luminescence properties of colloidal quantum dots have found applications in imaging, displays, light-emitting diodes and lasers, and single photon sources. Despite wide interest, several experimental observations in low-temperature photoluminescence of these quantum dots, such as the short lifetime on the scale of microseconds and a zero-longitudinal optical phonon line in spectrum, both attributed to a dark exciton in literature, remain unexplained by existing models. Here we propose a theoretical model including the effect of solid-state environment on luminescence. The model captures both coherent and incoherent interactions of band-edge exciton with phonon modes. Our model predicts formation of dressed states by coupling of the exciton with a confined acoustic phonon mode, and explains the short lifetime and the presence of the zero-longitudinal optical phonon line in the spectrum. Accounting for the interaction of the exciton with bulk phonon modes, the model also explains the experimentally observed temperature-dependence of the photoluminescence decay dynamics and temperature-dependence of the photoluminescence spectrum. |
format | Online Article Text |
id | pubmed-5976793 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2018 |
publisher | Nature Publishing Group UK |
record_format | MEDLINE/PubMed |
spelling | pubmed-59767932018-05-31 Polarons Explain Luminescence Behavior of Colloidal Quantum Dots at Low Temperature Khosla, Meenakshi Rao, Sravya Gupta, Shilpi Sci Rep Article Luminescence properties of colloidal quantum dots have found applications in imaging, displays, light-emitting diodes and lasers, and single photon sources. Despite wide interest, several experimental observations in low-temperature photoluminescence of these quantum dots, such as the short lifetime on the scale of microseconds and a zero-longitudinal optical phonon line in spectrum, both attributed to a dark exciton in literature, remain unexplained by existing models. Here we propose a theoretical model including the effect of solid-state environment on luminescence. The model captures both coherent and incoherent interactions of band-edge exciton with phonon modes. Our model predicts formation of dressed states by coupling of the exciton with a confined acoustic phonon mode, and explains the short lifetime and the presence of the zero-longitudinal optical phonon line in the spectrum. Accounting for the interaction of the exciton with bulk phonon modes, the model also explains the experimentally observed temperature-dependence of the photoluminescence decay dynamics and temperature-dependence of the photoluminescence spectrum. Nature Publishing Group UK 2018-05-30 /pmc/articles/PMC5976793/ /pubmed/29849075 http://dx.doi.org/10.1038/s41598-018-26678-w Text en © The Author(s) 2018 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. |
spellingShingle | Article Khosla, Meenakshi Rao, Sravya Gupta, Shilpi Polarons Explain Luminescence Behavior of Colloidal Quantum Dots at Low Temperature |
title | Polarons Explain Luminescence Behavior of Colloidal Quantum Dots at Low Temperature |
title_full | Polarons Explain Luminescence Behavior of Colloidal Quantum Dots at Low Temperature |
title_fullStr | Polarons Explain Luminescence Behavior of Colloidal Quantum Dots at Low Temperature |
title_full_unstemmed | Polarons Explain Luminescence Behavior of Colloidal Quantum Dots at Low Temperature |
title_short | Polarons Explain Luminescence Behavior of Colloidal Quantum Dots at Low Temperature |
title_sort | polarons explain luminescence behavior of colloidal quantum dots at low temperature |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5976793/ https://www.ncbi.nlm.nih.gov/pubmed/29849075 http://dx.doi.org/10.1038/s41598-018-26678-w |
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