Advanced VO2-Graphene based compact THz absorber for EM shielding and biosensing applications

This paper presents a compact, metal-free THz absorber utilizing VO 2 and graphene, offering ultra-wideband absorption (1.0702–13.3 THz) in the conducting state of VO 2 and narrow absorption at 6.81 THz in the insulating state. The absorber is tunable by adjusting the chemical potential of graphene and remains polarization-insensitive with over 80% absorption at incidence angles up to 70°. It demonstrates switching between conducting and insulating states, validated through an equivalent electric circuit model. The absorber’s applications include EM interference shielding, stealth, and biosensing, with high sensitivity, figure of merit, and quality factor for detecting cancerous cells and viruses.