Enhanced polarization conversion and giant Faraday rotation in patterned terahertz graphene metamaterials with combined electrical and magnetic tuning

Abstract

Graphene metamaterials (MMs) have the potential to reconfigure and dynamically control terahertz (THz) waves. In this study, we conducted numerical investigations to explore the effects of externally applied magnetic fields up to 20 Tesla on the transmission properties of graphene patterned split ring resonator (GSRR) MMs in the THz region. We quantitatively compared the tunability of resonance amplitude and frequency in the co-polarized transmission component between the magnetic method and the traditional electrical approach. Our results demonstrate that magnetic tuning can effectively modulate the resonant properties of GSRR MMs. Furthermore, when combining electrical and magnetic tuning, we observed an enhancement in the polarization conversion ratio, as well as the achievement of a significant Faraday rotation angle of nearly 90 degrees in GSRR MMs. These findings indicate the potential of functional graphene-based THz devices, including switches, modulators, polarization converters, and sensors.