Ultrathin microwave absorbers made of mu-near-zero metamaterials

TL;DR

This paper presents an ultrathin microwave absorber using mu-near-zero metamaterials, achieving high efficiency and polarization insensitivity at low frequencies, with potential advantages over traditional absorbers.

Contribution

Introduces a novel ultrathin microwave absorber based on MNZ metamaterials with high efficiency and polarization insensitivity at microwave frequencies.

Findings

Absorption efficiency exceeds 90% at 1.7 GHz

Achieves high performance at large incident angles

Designs are polarization-insensitive

Abstract

In this paper, mu-near-zero (MNZ) metamaterials are utilized to achieve an ultrathin absorber with a thickness of only about one percent of the operating wavelength. The metamaterial absorber (MA) is made of double-layered metallic spiral arrays designed to have a large purely imaginary permeability at low microwave frequencies (~ 1.7 GHz). An absorption efficiency above 90% is demonstrated at illumination angles up to 60 degrees. A polarization-insensitive MA implemented by 2D isotropic metamaterials is also studied. Our designs have great application potential as compared with the traditional heavy and thick absorbers made of natural materials working at the same frequencies.