Ultra-subwavelength thickness for dual/triple-band metamaterial absorber at very low frequency

Bui Xuan Khuyen,Youngpak Lee,Ji Sub Hwang,Vu Dinh Lam,Bui Son Tung,Yong Hwan Kim,Young Ju Kim,Ki Won Kim,Joo Yull Rhee

doi:10.1038/s41598-018-29896-4

Abstract

An integrated model utilizing external parasitic capacitors for a dual-band metamaterial perfect absorber (DMPA) is proposed and demonstrated in the UHF radio band. By adjusting the lumped capacitors on a simple meta-surface, the thickness of absorber is reduced to be only 1/378 and 1/320 with respect to the operating wavelength at 305 and 360.5 MHz, respectively. The simulations and the experiments confirm that the DMPA can maintain an absorption over 91% in a wide range of incident angle (up to 55°) and independent of the polarization of incident radiation. Additionally, we examine the integrated model for smaller dual-band absorber and absorption performance at higher frequencies (LTE band). Finally, we consolidate our approach by fabricating an ultrathin triple-band perfect absorber miniaturized to be only 1/591 of the longest operating wavelength. Our work is expected to contribute to the actualization of metamaterial-based devices working at radio frequency.

Highlights

IntroductionTechnology has been developed rapidly owing to the advances in material science
In recent years, technology has been developed rapidly owing to the advances in material science
We introduce and investigate, first of all, an ultrathin dual-band MM perfect absorber (MPA) (DMPA) that operates in sync with peripheral capacitors

Summary

Introduction

Technology has been developed rapidly owing to the advances in material science. In looking for new exciting materials and effects, an artificial material named “metamaterial” (MM) was realized and has changed our understanding of light-matter interactions in nature[1,2] The mechanism of these MMs, whose unit cells (so-called meta-atoms) are much smaller than the operating wavelength, is combined with the theory of effective medium[3]. Multi-band absorption based on ultrathin MPAs are still an important target to improve the future meta-instruments for telecommunication systems. For this purpose, we introduce and investigate, first of all, an ultrathin dual-band MPA (DMPA) that operates in sync with peripheral capacitors. By adding-on lumped capacitors to the basic DMPA, an ultrathin triple-band MPA is realized and investigated in the radio band

Methods

Results

Conclusion