Abstract
Plasmonic nanocavity arrays were achieved by producing isolated silver semi-cylindrical nanoshells periodically on a continuous planar gold film. Hybridization between localized surface plasmon resonance (LSPR) in the Ag semi-cylindrical nanoshells (SCNS) and surface plasmon polaritons (SPP) in the gold film was observed as split bonding and anti-bonding resonance modes located at different spectral positions. This led to strong local field enhancement and confinement in the plano-concave nanocavites. Narrow-band optical extinction with an amplitude as high as 1.5 OD, corresponding to 97% reduction in the transmission, was achieved in the visible spectrum. The resonance spectra of this hybrid device can be extended from the visible to the near infrared by adjusting the structural parameters.
Highlights
Plasmonic hybridization enhanced by nanocavity confinement
The “nanocavity” effect refers to the enhanced confinement of optical electric field in the enclosed space by the SCNS and the gold film through plasmonic hybridization
The remaining photoresist between the grating and the gold film was defined as the spacer layer
Summary
When an infinite gold film is inserted underneath the SCNSs facing the concaved side of the SCNSs to form nanocavities, strong interaction between the SCNSs and the Au film was induced, so that both the charge-density and near-field distribution are strongly modulated in the SCNSs and the Au film Interaction between the Ag SCNS and the Au film led to anti-bonding and bonding hybridization between the LSPR and propagating SPP within two different spectra with high efficiency These two hybrid plasmons can be tuned in spectroscopic response by changing the spacer thickness, the nanocavity length, and angle of incidence. The high-efficiency and highly tunable hybrid plasmons presented in this work are important for exploring high-sensitivity biosensors, high-efficiency optical notch filters, and ultrafast optical switching devices
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.