Active control of broadband plasmon-induced transparency in a terahertz hybrid metal-graphene metamaterial.

Zhaojian Zhang,Junbo Yang,Xin He,Jie Huang,Yunxin Han,Dingbo Chen,Jingjing Zhang,Siyu Xu

doi:10.1039/c8ra04329a

Zhaojian Zhang, Junbo Yang + Show 6 more

Open Access

https://doi.org/10.1039/c8ra04329a

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Journal: RSC advances	Publication Date: Jan 1, 2018
Citations: 26	License type: CC BY 3.0

Affiliation: National University of Defense Technology

Abstract

A hybrid metal–graphene metamaterial (MM) is reported to achieve active control of broadband plasmon-induced transparency (PIT) in the THz region. The unit cell consists of one cut wire (CW), four U-shaped resonators (USRs) and monolayer graphene sheets under the USRs. Via near-field coupling, broadband PIT can be produced through the interference between different modes. Based on different arrangements of graphene positions, not only can we achieve electrical switching of the amplitude of broadband PIT, but can also realize modulation of the bandwidth of the transparent window. Simultaneously, both the capability and region of slow light can be dynamically tunable. This work provides schemes to manipulate PIT with more degrees of freedom, which will find significant applications in multifunctional THz modulation.

Highlights

Electromagnetically-induced transparency (EIT) is a quantum phenomenon coming from the interference between two different excitation pathways in a three-level atomic system,[1] and the strong dispersion within the transparent window can have promise for applications in slow light and nonlinear effect enhancement.[2,3] the experimental conditions of EIT, such as stable pumping and low temperature,[1] restrict its further extensive application
We report a hybrid metal–graphene MM to achieve the active control of the broadband plasmon-induced transparency (PIT) in THz region
At rst, three kinds of MMs without graphene are simulated to investigate the mechanism of PIT, the unit cell of each MM only consists of a cut wire (CW), a U-shape resonators (USRs) and a CW coupled with one USR, Fig. 3 The mode (Ez) distribution corresponding to (a) a CW coupled with one USR at 1 THz. (b and c) A CW coupled with two USRs on the lower side at 0.9 THz and 1 THz, respectively. (d and e) A CW coupled with two USRs on the left side at 1.05 THz and 0.95 THz, respectively. (f and g) A CW coupled with four USRs at 0.95 THz and 1.05 THz, respectively

Summary

Introduction

Electromagnetically-induced transparency (EIT) is a quantum phenomenon coming from the interference between two different excitation pathways in a three-level atomic system,[1] and the strong dispersion within the transparent window can have promise for applications in slow light and nonlinear effect enhancement.[2,3] the experimental conditions of EIT, such as stable pumping and low temperature,[1] restrict its further extensive application.

Results

Conclusion