Controllable graphene W-shaped three-port THz circulator

Dmitriev, Victor; Castro, Wagner; Melo, Geraldo; Oliveira, Cristiano Braga de

doi:10.1016/j.photonics.2020.100795

Cited by 5 publications

(1 citation statement)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For designing a pre-optimization model of our THz graphene dipole antenna, resonating at

THz, a high level of efficiency must be assured. It is known that, for low THz applications, the width of graphene nanoribbons should measure tens of micrometers because the imaginary part of the effective refractive index is importantly reduced by increasing the graphene sheet width [ 51 ]. As a consequence, the radiation efficiency of the graphene dipole antenna also substantially improves with dipole width in the THz range from approximately 16% to 80%, at resonance frequency, by increasing the dipole width from 2

to 32

(with

eV and

) [ 41 ].…”

Section: Pre-optimization Design Of Graphene Dipole Antenna (Without ...mentioning

confidence: 99%

Multifunctional THz Graphene Antenna with 360∘ Continuous ϕ-Steering and θ-Control of Beam

Dmitriev

Oliveira

Paiva

et al. 2023

Sensors

Self Cite

View full text Add to dashboard Cite

A novel graphene antenna composed of a graphene dipole and four auxiliary graphene sheets oriented at 90∘ to each other is proposed and analyzed. The sheets play the role of reflectors. A detailed group-theoretical analysis of symmetry properties of the discussed antennas has been completed. Through electric field control of the chemical potentials of the graphene elements, the antenna can provide a quasi-omnidirectional diagram, a one- or two-directional beam regime, dynamic control of the beam width and, due to the vertical orientation of the dipole with respect to the base substrate, a 360∘ beam steering in the azimuth plane. An additional graphene layer on the base permits control of the radiation pattern in the θ-direction. Radiation patterns in different working states of the antenna are considered using symmetry arguments. We discuss the antenna parameters such as input reflection coefficient, total efficiency, front-to-back ratio, and gain. An equivalent circuit of the antenna is suggested. The proposed antenna operates at frequencies between 1.75 THz and 2.03 THz. Depending on the active regime defined by the chemical potentials set on the antenna graphene elements, the maximum gain varies from 0.86 to 1.63.