Multi-wavelength selective thermal emission enabled by dual-layer metasurface utilizing localized surface plasmon polariton resonance

Thermal emission is a ubiquitous electromagnetic wave with an extremely broad spectrum in nature, and controlling thermal emission can be used to develop low-cost and convenient infrared light sources with wavelength tunable in a wide range that is currently difficult for other sources. Conventional metasurfaces are commonly used to control light but lack the flexibility to achieve complex emission spectral profiles and dynamic tuning. Here, we introduce what we believe to be a novel dual-layer metasurface structure with two completely independent layers to achieve a multi-peak thermal emission within the 5-8 µm wavelength range. Simulations and experiments show that this two-layer structure can achieve arbitrary spectral shapes without interfering with multiple resonant modes. This unique configuration presents a promising platform for further exploration in thermal emission engineering.