Download all files (2.82 MB)

Collection

Citation

Description:

Photonic resonance modes can be spectrally coupled to the vibrational modes of molecules in the mid-infrared regime through interactions between localized electric fields and nearby molecules. According to recent studies, radiative loss engineering of coupled systems is a promising approach for tailoring coupling conditions and enhancing the molecular signals. However, this strategy has only been realized using the localized surface plasmon resonances of metal nanostructures, which suffer from increased ohmic loss in the mid-infrared region and face serious limitations in achieving high quality (Q) factors. In this study, we adopt silicon-based metasurfaces formed on silicon-on-insulator wafers to achieve high Q factors and tune the coupling conditions between the quasi-bound states in the continuum (qBICs) and molecular vibrations. The coupling between the resonance mode and polymethyl methacrylate molecules is tailored from weak to strong coupling regimes by simply changing the structural asymmetry parameter and utilizing the intrinsically high Q factors of the qBIC modes. In addition, we identify the optimal asymmetry parameter that maximizes the enhanced molecular signal, opening a route toward realizing highly sensitive surface-enhanced infrared spectroscopy using complementary metal-oxide semiconductor compatible all-dielectric materials.

Rights:

• Creative Commons BY Attribution 4.0 International
  

Keyword: BIC, metasurfaces, SEIRA, spectroscopy, strong coupling

Date published: 2023-10-27

Publisher: Wiley

Journal:

• Advanced Optical Materials (ISSN: 21951071) vol. 12 issue. 6 2301912

Funding:

• Japan Society for the Promotion of Science JP22K20496

Manuscript type: Publisher's version (Version of record)

MDR DOI:

First published URL: https://doi.org/10.1002/adom.202301912

Related item:

Other identifier(s):

Contact agent:

Updated at: 2024-04-04 08:30:24 +0900

Published on MDR: 2024-04-04 08:30:24 +0900