Optical Chirality of Gold Chiral Helicoid Nanoparticles in the Strong Coupling Region
The far- and near-field chirality properties are usually characterized by circular dichroism (CD) and optical chirality (OC), respectively. As a light–matter interaction for the hybrid states consisting of plasmons and excitons, the strong coupling interactions can affect the original chiral electro...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-02-01
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| Series: | Photonics |
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| Online Access: | https://www.mdpi.com/2304-6732/10/3/251 |
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| author | Haowei Cheng Kun Liang Xuyan Deng Lei Jin Jingcheng Shangguan Jiasen Zhang Jiaqi Guo Li Yu |
| author_facet | Haowei Cheng Kun Liang Xuyan Deng Lei Jin Jingcheng Shangguan Jiasen Zhang Jiaqi Guo Li Yu |
| author_sort | Haowei Cheng |
| collection | DOAJ |
| description | The far- and near-field chirality properties are usually characterized by circular dichroism (CD) and optical chirality (OC), respectively. As a light–matter interaction for the hybrid states consisting of plasmons and excitons, the strong coupling interactions can affect the original chiral electromagnetic modes. However, there are few works on this influence process, which prevents an in-depth understanding of chirality. Here, we theoretically investigate both the far-field and near-field characteristics of the chiral plasmonic gold helicoid nanoparticle (GHNP) to explore the chirality mechanism further. We found that the electromagnetic field distribution of GHNP consists of one dark mode and two bright modes. The dark mode is observed more clearly in CD than in extinction spectra. Two bright modes can strongly couple with excitons respectively, which is confirmed by the anticrossing behavior and mode splitting exhibited in the extinction and CD spectra. We also analyzed the near-field OC distribution of the GHNP hybrid system and obtained the chiral responses as well as the spectral correspondence between OC and CD. Furthermore, although the strong coupling interaction changes the energy levels, resulting in mode splitting, the chiral hotspot distributions of both the upper polariton branch and lower polariton branch are consistent with the original bright mode in OC maps. Our findings provide guidance for the design of structures with strong chiral responses and enhance the comprehension of chiral strong coupling systems. |
| first_indexed | 2024-03-11T06:00:55Z |
| format | Article |
| id | doaj.art-2390c5d018064fd2bf85b4265d91db31 |
| institution | Directory Open Access Journal |
| issn | 2304-6732 |
| language | English |
| last_indexed | 2024-03-11T06:00:55Z |
| publishDate | 2023-02-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Photonics |
| spelling | doaj.art-2390c5d018064fd2bf85b4265d91db312023-11-17T13:18:24ZengMDPI AGPhotonics2304-67322023-02-0110325110.3390/photonics10030251Optical Chirality of Gold Chiral Helicoid Nanoparticles in the Strong Coupling RegionHaowei Cheng0Kun Liang1Xuyan Deng2Lei Jin3Jingcheng Shangguan4Jiasen Zhang5Jiaqi Guo6Li Yu7State Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, ChinaState Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, ChinaState Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, ChinaState Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, ChinaState Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, ChinaState Key Laboratory for Artificial Microstructures and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, ChinaState Key Laboratory for Artificial Microstructures and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, ChinaState Key Laboratory of Information Photonics and Optical Communications, School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, ChinaThe far- and near-field chirality properties are usually characterized by circular dichroism (CD) and optical chirality (OC), respectively. As a light–matter interaction for the hybrid states consisting of plasmons and excitons, the strong coupling interactions can affect the original chiral electromagnetic modes. However, there are few works on this influence process, which prevents an in-depth understanding of chirality. Here, we theoretically investigate both the far-field and near-field characteristics of the chiral plasmonic gold helicoid nanoparticle (GHNP) to explore the chirality mechanism further. We found that the electromagnetic field distribution of GHNP consists of one dark mode and two bright modes. The dark mode is observed more clearly in CD than in extinction spectra. Two bright modes can strongly couple with excitons respectively, which is confirmed by the anticrossing behavior and mode splitting exhibited in the extinction and CD spectra. We also analyzed the near-field OC distribution of the GHNP hybrid system and obtained the chiral responses as well as the spectral correspondence between OC and CD. Furthermore, although the strong coupling interaction changes the energy levels, resulting in mode splitting, the chiral hotspot distributions of both the upper polariton branch and lower polariton branch are consistent with the original bright mode in OC maps. Our findings provide guidance for the design of structures with strong chiral responses and enhance the comprehension of chiral strong coupling systems.https://www.mdpi.com/2304-6732/10/3/251chiral nanoparticleoptical chiralitycircular dichroismplasmonstrong coupling |
| spellingShingle | Haowei Cheng Kun Liang Xuyan Deng Lei Jin Jingcheng Shangguan Jiasen Zhang Jiaqi Guo Li Yu Optical Chirality of Gold Chiral Helicoid Nanoparticles in the Strong Coupling Region Photonics chiral nanoparticle optical chirality circular dichroism plasmon strong coupling |
| title | Optical Chirality of Gold Chiral Helicoid Nanoparticles in the Strong Coupling Region |
| title_full | Optical Chirality of Gold Chiral Helicoid Nanoparticles in the Strong Coupling Region |
| title_fullStr | Optical Chirality of Gold Chiral Helicoid Nanoparticles in the Strong Coupling Region |
| title_full_unstemmed | Optical Chirality of Gold Chiral Helicoid Nanoparticles in the Strong Coupling Region |
| title_short | Optical Chirality of Gold Chiral Helicoid Nanoparticles in the Strong Coupling Region |
| title_sort | optical chirality of gold chiral helicoid nanoparticles in the strong coupling region |
| topic | chiral nanoparticle optical chirality circular dichroism plasmon strong coupling |
| url | https://www.mdpi.com/2304-6732/10/3/251 |
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