Abstract-Plasmon-induced transparency in graphene-based terahertz metamaterials

Koijam Monika Devi, Maidul Islam, Dibakar Roy Chowdhury, Amarendra K. Sarma,  Gagan Kumar,


http://iopscience.iop.org/article/10.1209/0295-5075/120/27005/meta


Plasmon-induced transparency (PIT) effect in a terahertz graphene metamaterial is numerically and theoretically analyzed. The proposed metamaterial comprises of a pair of graphene split ring resonators placed alternately on both sides of a graphene strip of nanometer scale. The PIT effect in the graphene metamaterial is studied for different vertical and horizontal configurations. We have shown that the PIT effect can be tuned by varying the Fermi energy of the graphene layer. A theoretical model using the three-level plasmonic system is established in order to validate the numerical results. Our studies could be significant in designing graphene-based frequency agile ultra-thin devices for terahertz applications.

Abstract-Plasmon induced transparency in graphene based terahertz metamaterials

Koijam Monika Devi, M. Islam, Dibakar R. Chowdhury, Amarendra K. Sarma, Gagan Kumar

https://arxiv.org/abs/1711.03775

Plasmon induced transparency (PIT) effect in a terahertz graphene metamaterial is numerically and theoretically analyzed. The proposed metamaterial comprises of a pair of graphene split ring resonators placed alternately on both sides of a graphene strip of nanometer scale. The PIT effect in the graphene metamaterial is studied for different vertical and horizontal configurations. Our results reveal that there is no PIT effect in the graphene metamaterial when the centers of both the split ring resonators and the graphene strip are collinear to each other. This is a noteworthy feature, as the PIT effect does not vanish for similar configuration in a metal-based metamaterial structure. We have further shown that the PIT effect can be tuned by varying the Fermi energy of graphene layer. A theoretical model using the three level plasmonic system is established in order to validate the numerical results. Our studies could be significant in designing graphene based frequency agile ultra-thin devices for terahertz applications.

Abstract-Plasmon induced transparency effect through alternately coupled resonators in terahertz metamaterial

Koijam Monika Devi, Amarendra K. Sarma, Dibakar Roy Chowdhury, and Gagan Kumar

https://www.osapublishing.org/oe/abstract.cfm?uri=oe-25-9-10484

We analyze plasmon induced transparency (PIT) in a planar terahertz metamaterial comprising of two C-shaped resonators and a cut-wire. The two C-shaped resonators are placed alternately on both sides of the cut-wire such that it exhibits a PIT effect when coupled with the cut wire. We have further shown that the PIT window is modulated by displacing the C-shaped resonators w.r.t. the cut-wire. A lumped element equivalent circuit model is reported to explain the numerical observations for different coupling configurations. The PIT effect is further explored in a metamaterial comprising of a cross like structure and four C-shaped resonators. For this configuration, the PIT effect is studied for the incident light polarized in both x and y directions. It is observed that such a structure exhibits equally strong PIT effects for both the incident polarizations, indicating a polarization independent response to the incident terahertz radiation. Our study could be significant in the development of slow light devices and polarization independent sensing applications.