Lithography-Free, Manganese-Based Ultra-Broadband Absorption Through Annealing-Based Deformation of Thin Layers into metal-air composites

TL;DR

This paper presents a cost-effective, lithography-free ultra-broadband absorber using annealed manganese-based metal-insulator-metal layers, achieving over 94% absorption across 450-1400 nm with high polarization and angular stability.

Contribution

It introduces a novel manganese-based MIM structure with annealing-induced deformation for ultra-broadband absorption, emphasizing simplicity and suitability for large-scale production.

Findings

Achieves over 94% absorption in 450-1400 nm range.

Maintains high absorption for TM polarization up to 70° and TE up to 50°.

Uses a simple, cost-effective annealed tri-layer MIM configuration.

Abstract

Fabrication, characterization, and analysis of an ultra-broadband lithography-free absorber is presented. An over 94% average absorption is experimentally achieved in the wavelength range of 450-1400 nm. This ultra-broadband absorption is obtained by a simple annealed tri-layer metal-insulator-metal (MIM) configuration. The metal used in the structure is Manganese (Mn), which also makes the structure cost-effective. It is shown that the structure retains its high absorption for TM polarization, up to 70 degrees, and, for TE polarization, up to 50 degrees. Moreover, the physical mechanism behind this broadband absorption is explained. Being both lithography-free and cost-effective, the structure is a perfect candidate for large-area and mass production purposes.