Dynamically tunable multiple surface lattice resonances in overlapping gold nanodisk arrays

Area of Science:

• Plasmonics
• Nanophotonics
• Materials Science

Background:

• Noble metal nanoparticle arrays support surface lattice resonances (SLRs), crucial for nanophotonic devices.
• Controlling and tuning multiple resonant modes in these systems remains a significant challenge.

Purpose of the Study:

• To fabricate and investigate overlapping gold nanodisk arrays for simultaneous excitation of multiple SLRs.
• To demonstrate a robust and tunable multi-resonant plasmonic platform for advanced applications.

Main Methods:

• Fabrication of overlapping gold nanodisk arrays with varying lattice periods.
• Analysis of transmission spectra and near-field distributions.
• Characterization of refractive-index sensing performance and mechanical tuning capabilities.

Main Results:

• Simultaneous excitation of multiple well-defined SLRs achieved within a single platform.
• Weak inter-mode coupling and strong fabrication tolerance observed in the hybrid configuration.
• High-performance multi-wavelength refractive-index sensing demonstrated (max sensitivity 755 nm/RIU, FOM 101).

Conclusions:

• Overlapping plasmonic lattices provide a robust multi-band platform for nanophotonic devices.
• The developed structure enables active control and dynamic tuning of multiple SLRs.
• This approach bridges theoretical design with practical implementation for sensing and reconfigurable devices.