Probing the kinetic evolution of nanoparticle (NP) growth in liquids is essential for understanding complex nano-phases and their corresponding functions. Terahertz (THz) sensing, an emerging technology for next-generation laser photonics, has been developed with unique photonic features, including label-free, non-destructive, and molecular-specific spectral characteristics. Recently, metasurface-based sensing platforms have helped trace biomolecules by overcoming low THz absorption cross-sectional limits. However, the direct probing of THz signals in aqueous environments remains difficult. Here, the authors report that vertically aligned nanogap-hybridized metasurfaces can efficiently trap traveling NPs in the sensing region, thus enabling us to monitor the real-time kinetic evolution of NP assemblies in liquids. The THz photonics approach, together with an electric tweezing technique via spatially matching optical hotspots to particle trapping sites with a nanoscale spatial resolution, is highly promising for underwater THz analysis, forging a route toward unraveling the physicochemical events of nature within an ultra-broadband wavelength regime.
Bibliographical noteFunding Information:
This work was supported in part by KIST intramural Grant (Nos. 2E31251, 2E31253, and 2E30271), and the Joint research lab program of the National Agenda research division, KIST. Y.-S.R. acknowledges the support from the National Research Foundation of Korea (NRF) (NRF-2020M3H5A1081103). M.S. acknowledges the support from the National Research Foundation of Korea (NRF) (NRF-2020R1A2C2007077 and the Global Frontier Program CAMM-2019M3A6B3030638). They would like to thank Editage (www.editage.co.kr) for English language editing.
© 2021 The Authors. Advanced Science published by Wiley-VCH GmbH
- nanophotonics and plasmonics
- nanoscale electrical tweezers
- optical biosensors
- terahertz optics
ASJC Scopus subject areas
- Medicine (miscellaneous)
- Chemical Engineering(all)
- Materials Science(all)
- Biochemistry, Genetics and Molecular Biology (miscellaneous)
- Physics and Astronomy(all)