Graphene-enabled terahertz dielectric rod antenna with polarization reconfiguration

In this article, magnetically biased graphene is utilized to achieve a terahertz antenna capable of reconfiguring the polarization of the radiation pattern, transitioning between two states of linear and circular polarizations. The antenna is structured in a way that allows terahertz waves to enter through a slot aperture from a microstrip transmission line. These waves are then coupled to a silicon dielectric resonator, which has a graphene layer on top of it. Subsequently, the terahertz surface waves are launched within the silicon dielectric rod by the dielectric resonator. By applying a biased magnetic field perpendicular to the antenna, the conductivity tensor of graphene exhibits non-diagonal elements. This results in the production of circular polarization within the antenna. Furthermore, altering the direction of the applied bias magnetic field causes a shift in polarization from right-hand circularly polarized to left-hand circularly polarized. The modified relaxation-effect model is employed at terahertz frequencies to calculate the losses of silver metal, deviating from the accurate skin effect model used for microwave frequencies. Remarkable impedance matching is attained for linear and circular polarization within the range of 2.86 to 3.14 THz. The article provides detailed insights into the simulated reflection coefficient, axial ratio, gain, and radiation patterns. This device holds the potential for integration into diverse subwavelength terahertz systems.

Automated summary

In this article, a magnetically biased graphene is used to create a terahertz antenna that can reconfigure the polarization of the radiation pattern. By altering the direction of the applied magnetic field, the polarization can be shifted from right-hand circularly polarized to left-hand circularly polarized. This device shows potential for integration into various subwavelength terahertz systems.