Design of a high-efficient metamaterial X-band absorber composed of a dielectric cylinder combined with a thin magnetic cylinder unit

Abstract

High-efficient microwave absorbers (MAs) with excellent absorption performance and lightweight characteristics have important applications in the military and civil. Here, we propose a dielectric-magnetic hybrid microwave absorber composed of a lattice of dielectric cylinders combined with thin magnetic cylinders backed by a perfect electrical conductor ground plane. The dielectric material that is designed as the dielectric cylinder is based on multi-walled carbon nanotubes-epoxy (MWCNT-EP). The MWCNT-EP is prepared and the S-parameters are measured by the standard transmission/reflection (T/R) method. The thin magnetic cylinder is based on a commercial magnetic material with a height of only 1 mm. With the coaction of magnetic loss and dielectric loss, the proposed microwave absorber’s reflection loss is less than −20 dB under normal incident with a total height of 5 mm in the X-band. Besides, the dielectric-magnetic microwave absorber can maintain good absorption performance with different incident angles and polarizations. In this work, we provide a method to combine the properties of magnetic and dielectric material to construct the MA with high-efficient absorption performance.