Polarization-Insensitive Near Perfect Tunable Graphene-Based Metamaterial Absorber

A novel metal-insulator-metal (MIM) near-perfect metamaterial (MM) absorber based on graphene functioning at mid-infrared (MIR) regime was designed, and it’s absorption properties were studied here, along with strategies to improve and refine the absorber’s absorption. The absorber’s framework held a square-triangle configured resonator combining miniature L-shaped construction at the two corners composed of Cu, creating a metallic MM layer on top of the absorber. A graphene sheet was sandwiched within the top Cu MM and dielectric surfaces to improve absorbance and unleash precise tunability. The absorber showed a nearly ideal 98.38% peak absorption, including the potential for architectural and intangible deviations to cause a peak frequency shift of >25 THz, displaying potentiality in glucose detection having a sensitivity of 10.10 THz/RIU. Furthermore, it was discovered that the suggested absorber functioned exceptionally well at greater incidence angles, being polarization-independent. This presents a strong prospect of developing graphene-based MIM MM absorbers for various optoelectronic and photonic applications.