Lithography-free Kirchhoff's Metasurfaces

TL;DR

This paper presents a lithography-free, multi-layer metasurface designed for engineered electromagnetic absorption in the mid-infrared range, combining experimental and simulation analyses to guide absorber and emitter applications.

Contribution

It introduces a novel fabrication approach for multilayer metasurfaces with tailored absorption properties, validated through experiments and simulations.

Findings

Demonstrated engineered absorption in the mid-infrared range.

Validated simulation results with experimental measurements.

Provided design guidelines for absorber and emitter applications.

Abstract

Lithography-free metasurfaces composed of a nano-layered stack of materials are attractive not only due to their optical properties but also by virtue of fabrication simplicity and cost reduction of devices based on such structures. We demonstrate a multi-layer metasurface with engineered electromagnetic absorption in the mid-infrared (MIR) wavelength range. Characterisation of thin SiO$_2$ and Si films sandwiched between two Au layers by way of experimental absorption and thermal radiation measurements as well as finite difference time domain (FDTD) numerical simulations is presented. Comparison of experimental and simulation data of optical properties of multilayer metasurfaces show guidelines for the absorber/emitter applications.