Abstract
Transient atomic protrusions in plasmonic nanocavities confine optical fields to sub-1-nm3 picocavities, allowing the optical interrogation of single molecules at room temperature. While picocavity formation is linked to both the local chemical environment and optical irradiation, the role of light in localizing the picocavity formation is unclear. Here, we combine information from thousands of picocavity events and simultaneously compare the transient Raman scattering arising from two incident pump wavelengths. Full analysis of the data set suggests that light suppresses the local effective barrier height for adatom formation and that the initial barrier height is decreased by reduced atomic coordination numbers near facet edges. Modeling the system also resolves the frequency-dependent picocavity field enhancements supported by these atomic scale features.
Original language | English |
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Pages (from-to) | 2868-2875 |
Number of pages | 8 |
Journal | ACS Photonics |
Volume | 8 |
Issue number | 10 |
DOIs | |
Publication status | Published - 4 Oct 2021 |
Bibliographical note
Funding Information:Funding: We acknowledge support from European Research Council (ERC) under Horizon 2020 research and innovation programme PICOFORCE (grant agreement no. 883703) and POSEIDON (grant agreement no. 861950). We acknowledge funding from the EPSRC (Cambridge NanoDTC EP/L015978/1, EP/L027151/1, EP/S022953/1, EP/P029426/1, and EP/R020965/1). R.C. acknowledges support from Trinity College, University of Cambridge. B.d.N. acknowledges support from the Leverhulme Trust and Isaac Newton Trust in the form of an ECF.
Publisher Copyright:
© 2021 The Authors. Published by American Chemical Society.
Keywords
- adatom
- localization spectroscopy
- picocavity
- plasmonics
- SERS
ASJC Scopus subject areas
- Biotechnology
- Electronic, Optical and Magnetic Materials
- Atomic and Molecular Physics, and Optics
- Electrical and Electronic Engineering