Metasurface Broadband Solar Absorber

TL;DR

This paper presents a broadband, polarization-independent metasurface solar absorber with over 90% absorption efficiency across the visible and near-infrared spectrum, suitable for solar energy applications.

Contribution

It introduces a novel metasurface design with gold nano-resonators that achieves high absorption over wide angles and wavelengths, advancing solar absorber technology.

Findings

Achieves >90% absorptance in visible and near-infrared spectrum.

Maintains high performance over wide incidence angles and polarizations.

Potential application in solar thermophotovoltaics with refractory materials.

Abstract

We demonstrate a broadband, polarization independent, omnidirectional absorber based on a metallic metasurface architecture, which accomplishes greater than 90% absorptance in the visible and near-infrared range of the solar spectrum, and exhibits low emissivity at mid- and far-infrared wavelengths. The complex unit cell of the metasurface solar absorber consists of eight pairs of gold nano-resonators that are separated from a gold ground plane by a thin silicon dioxide spacer. Our experimental measurements reveal high-performance absorption over a wide range of incidence angles for both s- and p-polarizations. We also investigate numerically the frequency-dependent field and current distributions to elucidate how the absorption occurs within the metasurface structure. Furthermore, we discuss the potential use of our metasurface absorber design in solar thermophotovoltaics by exploiting refractory plasmonic materials.