Electromagnetically induced transparency metamaterial based on spoof localized surface plasmons at terahertz frequencies.

Zhen Liao,Tie Jun Cui,Shuo Liu,Biaobing Jin,Chun Li,Hui Feng Ma

doi:10.1038/srep27596

Abstract

We numerically and experimentally demonstrate a plasmonic metamaterial whose unit cell is composed of an ultrathin metallic disk and four ultrathin metallic spiral arms at terahertz frequencies, which supports both spoof electric and magnetic localized surface plasmon (LSP) resonances. We show that the resonant wavelength is much larger than the size of the unit particle, and further find that the resonant wavelength is very sensitive to the particle’s geometrical dimensions and arrangements. It is clearly illustrated that the magnetic LSP resonance exhibits strong dependence to the incidence angle of terahertz wave, which enables the design of metamaterials to achieve an electromagnetically induced transparency effect in the terahertz frequencies. This work opens up the possibility to apply for the surface plasmons in functional devices in the terahertz band.

Highlights

(EIT) metamaterial in the terahertz spectrum[28,29]
The structure of the designed localized surface plasmons (LSPs) particle is schematically illustrated in Fig. 1(a), which is composed of four gold spiral arms and one internal gold disk with ultrathin thickness 0.2 μm
We can see that the arrows go from left of the structure to right. This mode profiles correspond to the electric-dipole mode, indicating that the proposed structure supports spoof LSPs resonance at terahertz frequency

Summary

Introduction

(EIT) metamaterial in the terahertz spectrum[28,29]. Numerical simulations, experimental measurements are conducted to evaluate and validate the performance of the proposed spoof LSPs, promising in a number of potential terahertz applications such slow lights, filters, and sensing. This mode profiles correspond to the electric-dipole mode, indicating that the proposed structure supports spoof LSPs resonance at terahertz frequency. The resonance blue shifts (negative value in real parts of S) are the result of the radiative dipole interaction for bigger separations, whereas red shifts due to the static dipole coupling for smaller lattice spacing.

Results

Conclusion