Investigation of graphene fractal frequency selective surface loaded terahertz absorber

摘要

The voyage of the research in terahertz (THz) technology has an intriguing application in terahertz detection, and the graphene absorbers have dramatically enhanced the effectiv-ity, and the efficiency in its performance. Though, there is a need of wide angle insensible, polarization angle insensible, broadband terahertz metamaterial absorber (TMA) with reduced design complexity. Hence, in this research an effort has been carried out to develop such TMA with equivalent circuit modelling approach. A massive - 10 dB reflection coefficient (RC) bandwidth of 2.66 THz (1.08-3.74 THz) has been obtained by the proposed TMA device with two significant peaks of - 19.48 dB and -14.5 dB at 1.32 THz and 3.44 THz, respectively. The oblique incidence stability of the device has been verified by investigating the effect of wave incidence angle, and wave polarization angle in RC characteristic. Further, the physics behind the absorption has been systematically illustrated along with three different absorption mechanism, i.e., input-impedance matching mechanism, wave interference phenomena, and induced current model, that attest the Unprecedented absorption results. Moreover, the electrical parameters of the device (i.e., effective electric permittivity, and effective magnetic permeability) have been extracted to analyze the metamaterial behavior of the device. The results are good enough to explore the potential of the TMA for THz sensing applications.