# Selective-wavelength perfect infrared absorption in Ag@ZnO conical metamaterial structure

## TL;DR

A new metamaterial structure using silver and zinc oxide absorbs infrared light at specific wavelengths, useful for stealth technology.

## Contribution

A novel Ag@ZnO metamaterial design achieving high absorption at 1.7 µm and 6.5 µm for infrared stealth applications.

## Key findings

- The Ag@ZnO metamaterial achieved 93.1% and 93.5% absorption at 1.7 µm and 6.5 µm wavelengths.
- The structure reduces IR scattering and heat signatures, useful for evading laser-guided detection.
- Simulations using FDTD and FEM confirmed high absorptivity due to electric and magnetic dipole resonance.

## Abstract

We present a new selective Metamaterial Perfect Absorber (MPA) consisting of zinc oxide embedded silver (Ag@ZnO), designed for applications in infrared stealth technology. The numerical simulation included a wide frequency range from 1 to 1000 THz and shows that the design MPA structure presented two absorption peaks at the desired wavelengths of 1.7 µm and 6.5 µm. The absorptivity of both peaks reached approximately 93.1% and 93.5%. The first peak at 1.7 µm decreases the scattering of IR laser beams from the surface of the MPA structure and also lowers the infrared tracks that could direct laser-guided devices to its specific target. On the other hand, the second peak reduces the surface heat wave. The suggested MPA (Ag@ZnO) structure is activated by a plane wave using a full wave vector and a broad frequency domain solution. In the framework of computer simulation technology (CST) Microwave Studio, uses both Finite-Difference-Time-Domain (FDTD) and Finite-Element-Method (FEM) techniques to predict the optical behavior of the proposed MPA structure. Both peaks achieved a high value of absorptivity due to the simultaneous excitation of the electric and magnetic dipole at resonance wavelength.