Versatile design of tunable Faraday rotator for terahertz band using graphene-InSb-graphene and 1D photonic crystal

Abstract

Abstract A Faraday rotator, composed of graphene-InSb-graphene as magnetic floor and Si- S i O 2 materials as the non-magnetic floor is designed to operate at 10 THz frequency, promising for realizing future communication devices. The height of the dielectric layers significantly influences the selection of the resonance frequency. Additionally, the structure can be tuned to operate at a desired frequency thanks to the adjustable surface conductivity of graphene. The findings reveal that variations in the strength of the applied magnetic field intricately modulate the Faraday rotation (FR) and subsequently alter the transmission spectrum. Specifically, values exceeding 40 degrees of FR and a transmission rate of 50% were attainedwhen the magnetic field strength (B) was set at 2 Tesla. Finally, we have proposed a design process for a Faraday rotator that can operate at any arbitrary frequency in the THz band. This innovative design has the potential to introduce a novel approach in ultrathin magneto-optical nanophotonic devices, enabling the realization of polarization rotators characterized by elevated transmittance and reduced reliance on applied static magnetic fields within the THz band.