Optical detection of single sub-15 nm objects using elastic scattering strong coupling

MohammadReza Aghdaee, Melissa J. Goodwin and Oluwafemi S. Ojambati ()
Additional contact information
MohammadReza Aghdaee: University of Twente
Melissa J. Goodwin: University of Twente
Oluwafemi S. Ojambati: University of Twente

Nature Communications, 2025, vol. 16, issue 1, 1-10

Abstract: Abstract Metallic nano-objects play crucial roles in diverse fields, including biomedical imaging, nanomedicine, spectroscopy, and photocatalysis. Nano-objects smaller than 15 nm exhibit extremely low scattering cross-sections, posing a significant challenge for optical detection. An approach to enhance optical detection is to exploit nonlinearity of strong coupling regime, especially for elastic scattering, which is universal to all objects. However, there is still no observation of the strong coupling of elastic light scattering from nano-objects. Here, we demonstrate the strong coupling of elastic light scattering in self-assembled plasmonic nanocavities formed between a gold nanoprobe and a gold film. We employ this technique to detect individual objects with diameters down to 1.8 nm. The resonant mode of the nano-object in the nanocavity environment strongly couples with the nanocavity mode, revealing anti-crossing scattering modes under dark-field spectroscopy. The experimental result agrees with numerical calculations, which we use to extend this technique to other metals. Furthermore, our results show that scattering cross-section ratio of the nano-object scales with the electric field to fourth power, similar to surface-enhanced Raman spectroscopy. This work establishes a new possibility of elastic strong coupling and demonstrates its applicability for observing small, non-fluorescent, Raman inactive sub-15 nm objects, complementary to existing microscopes.

Date: 2025
References: Add references at CitEc
Citations:

Downloads: (external link)
https://www.nature.com/articles/s41467-025-63380-8 Abstract (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:nat:natcom:v:16:y:2025:i:1:d:10.1038_s41467-025-63380-8

Ordering information: This journal article can be ordered from
https://www.nature.com/ncomms/

DOI: 10.1038/s41467-025-63380-8

Access Statistics for this article

Nature Communications is currently edited by Nathalie Le Bot, Enda Bergin and Fiona Gillespie

More articles in Nature Communications from Nature
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().