Integrating lattice and gap plasmonic modes to construct dual-mode metasurfaces for enhancing light–matter interaction

Abstract

Photonic structures with optical resonances beyond a single controllable mode are strongly desired for enhancing light-matter interactions and bringing about advanced photonic devices. However, the realization of effective multimodal photonic structures has been restricted by the limited tunable range of mode manipulation, the spatial dispersions of electric fields or the polarization-dependent excitations. To overcome these limitations, we create a dualmode metasurface by integrating the plasmonic surface lattice resonance and the gap plasmonic modes; this metasurface offers a widely tunable spectral range, good overlap in the spatial distribution of electric fields, and polarization independence of excitation light. To show that such dual-mode metasurfaces are versatile platforms for enhancing lightmatter interactions, we experimentally demonstrate a significant enhancement of second-harmonic generation using our design, with a conversion efficiency of 1-3 orders of magnitude larger than those previously obtained in plasmonic systems. These results may inspire new designs for functional multimodal photonic structures.

An all-dielectric metasurface based on Fano resonance with tunable dual-peak insensitive polarization for high-performance refractive index sensing

“…Sensitivity ( S ) is a key index to judge the performance of RI sensors, which can be used to compare and evaluate the performance of different sensors. It can be defined by the following formula: 40 where Δ n is the RI variation, and Δ λ is the resonant peak shift. The sensitivity of the RI sensor is displayed in Fig.…”

“…Another important parameter to describe the abilities of the RI sensor is the figure of merit (FoM), and the formula is as follows: 40 …”

A planar plasmonic nano-gap and its array for enhancing light-matter interactions at the nanoscale

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Ultrasensitive Refractive Index Sensing Based on Hybrid High-Q Metasurfaces

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