Plasmon-exciton systems with high quantum yield using deterministic aluminium nanostructures with rotational symmetries

• Main Authors: Tobing, Landobasa Yosef Mario, Muhammad Danang Birowosuto, Fong, Kah Ee, Gao, Yuan, Tong, Jinchao, Suo, Fei, Dang, Cuong, Demir, Hilmi Volkan, Zhang, Dao Hua
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2021
• Subjects: Engineering::Electrical and electronic engineering; Aluminium; Plasmonic
• Online Access: https://hdl.handle.net/10356/150774
• Institution: Nanyang Technological University

The abundance and corrosion-resistant properties of aluminium, coupled with its compatibility to silicon processing make aluminium an excellent plasmonic material for light–matter interaction in the ultraviolet-visible spectrum. We investigate the interplay of the excitation and emission enhancements of quantum dots coupled with ultra-small aluminium nanoantennae with varying rotational symmetries, where emission enhancements of ∼8 and ∼6 times have been directly measured for gammadion and star-shaped structures. We observed spontaneous emission modification in the Al antenna with a C6 symmetry and deduce a Purcell factor in the range of 68.01 < FP < 118.25 at plasmonic hotspots, corresponding to a modified quantum yield of >89% in the single antenna and near-unity quantum yield at the plasmonic hotspots. This finding brings us a step closer towards the realization of circularly polarized nanoemitters.