Wideband perfect light absorber at midwave infrared using multiplexed metal structures

Area of Science:

• Optics and Photonics
• Materials Science
• Nanotechnology

Background:

• Plasmonic nanostructures offer unique light-matter interaction properties.
• Developing efficient and wideband light absorbers is crucial for various IR applications.
• Existing perfect light absorbers often have limited spectral bandwidth.

Purpose of the Study:

• To experimentally demonstrate a wideband near-perfect light absorber in the midwave infrared (IR) region.
• To investigate the performance of a multiplexed plasmonic metal structure for light absorption.
• To compare the absorption bandwidth of multiplexed versus non-multiplexed structures.

Main Methods:

• Fabrication of a multiplexed plasmonic metal structure consisting of different-sized gold squares on a dielectric layer and a thick metal backing.
• Experimental characterization of light absorption spectra in the midwave IR region.
• Fabrication and characterization of control samples with regular non-multiplexed structures.

Main Results:

• The multiplexed structure achieved near-perfect light absorption (over 98%).
• The absorber demonstrated wideband performance in the midwave IR spectrum.
• The multiplexed design exhibited a significantly wider absorption band compared to non-multiplexed structures.

Conclusions:

• Multiplexed plasmonic metal structures are highly effective for creating wideband near-perfect light absorbers.
• This technology holds promise for advanced applications in the midwave IR range.
• The demonstrated absorber design offers superior performance over conventional structures.