An electromagnetic modulator based on electrically controllable metamaterial analogue to electromagnetically induced transparency

Yuancheng Fan,Botao Kong,Quanhong Fu,Fuli Zhang,Jiajia Dong,Hongqiang Li,Tong Qiao

doi:10.1038/srep40441

Yuancheng Fan, Botao Kong + Show 5 more

Open Access

https://doi.org/10.1038/srep40441

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Abstract

Electromagnetically induced transparency (EIT) is a promising technology for the enhancement of light-matter interactions, and recent demonstrations of the EIT analogue realized in artificial micro-structured medium have remarkably reduced the extreme requirement for experimental observation of EIT spectrum. In this paper, we propose to electrically control the EIT-like spectrum in a metamaterial as an electromagnetic modulator. A diode acting as a tunable resistor is loaded in the gap of paired wires to inductively tune the magnetic resonance, which induces remarkable modulation on the EIT-like spectrum through the metamaterial sample. The experimental measurements confirmed that the prediction of electromagnetic modulation in three narrow bands on the EIT-like spectrum, and a modulation contrast of up to 31 dB was achieved on the transmission through the metamaterial. Our results may facilitate the study on active/dynamical technology in translational metamaterials, which connect extraordinary manipulations on the flow of light in metamaterials, e.g., the exotic EIT, and practical applications in industry.

Highlights

It from practical applications in our daily life
In EIT analogue, the EIT-like spectrum is achieved by properly tailoring the coherent interference between resonators, e.g., the EIT analogue was first demonstrated in a metamaterial composed of bright and dark resonators, the two resonators are in close proximity and strongly coupled to each other, the coupling or interaction between these two resonator are classical near-field coupling[40,41,42,43,44,45], while for the quantum EIT, the coupling between energy levels is implemented through a pump beam[32]
The dipolar mode is similar to the bright mode of the wire in the plasmonic induced transparency (PIT) study[32], which provides an opaque spectral range for the formation of EIT analogue

Summary

Introduction

It from practical applications in our daily life. Metamaterials provide the opportunities to realize classical analogue of quantum phenomena in various frequency band for that their optical properties can be freely tailored by designing the meta-atoms. Our numerical results indicate that the magnetic resonance of the wire pair can be excited near the resonant frequency of the electric mode (of the left single wire) by connecting the two discrete wires metallically (results are not shown here), these two modes will coherently interfere with each other and show EIT-like transmission spectrum.

Results

Conclusion