A novel graphene-based THz absorber using triangular split ring resonator for carcinoma detection

Abstract This study presents a novel graphene-based terahertz (THz) absorber for carcinoma detection, utilizing a triangular split ring resonator (TSRR) loaded on a central cross dipole. Each arm of the cross dipole is embedded with a triangular SRR, enhancing electromagnetic confinement and optimizing absorption efficiency. The absorber is developed using polyimide as the dielectric substrate, while graphene forms the top frequency-sensitive surface, ensuring high absorption performance. The proposed structure exhibits near-perfect absorption at 0.8 THz, with an absorptivity close to 100%. The estimated theoretical bandwidth of the absorber is 20 GHz with reference absorptivity of 90%. Comprehensive simulations and parametric studies demonstrate polarization-independent behaviour under transverse electric (TE) and transverse magnetic (TM) modes. Additionally, the structure maintains angular stability up to 75°, attributed to the compact design and symmetric configuration of the TSRR-loaded unit cell. The absorber is further explored for biomedical sensing applications, where it is configured as a carcinoma sensor by introducing an analyte layer. The sensor exhibits a high resonance shift-based sensitivity of 287 GHz/RIU, making it a promising candidate for highly sensitive THz biosensing. The proposed design offers a compact and highly efficient platform for cancer diagnostics and biomedical applications in the THz regime.