Stacked nanogap plasmons for multispectral photoluminescence

Area of Science:

• Photonics and Nanotechnology
• Optical Metamaterials
• Plasmonics

Background:

• Plasmonic metasurfaces are crucial for tailoring light-matter interactions at the nanoscale.
• Achieving multiple distinct optical resonances in a single metasurface is key for advanced photonic applications.

Purpose of the Study:

• To demonstrate doubly stacked nanogap arrays capable of supporting dual Fabry-Pérot resonances.
• To investigate the tunability of these resonances based on nanogap geometry.
• To explore the application of these dual resonances for multicolor photoluminescence enhancement.

Main Methods:

• Numerical simulations were employed to analyze the optical properties of the nanogap arrays.
• Fabrication involved alternating metal-insulator deposition, electron beam lithography, and ion milling.
• Photoluminescence spectroscopy was used to assess dye modification under dual plasmon resonance conditions.

Main Results:

• Doubly stacked nanogap arrays exhibited two distinct Fabry-Pérot resonances.
• Resonance wavelengths were found to differ due to lateral length variations in the nanogaps.
• Spectra of R6G and IR-820 dyes showed significant modifications near the dual resonance dips.

Conclusions:

• Stacked nanogap arrays offer a versatile platform for co-localized multicolor dye excitation.
• This technology facilitates multispectral photoluminescence engineering.
• Potential applications include multi-wavelength light sources and advanced multicolor displays.