Dual-core fiber biosensor with graphene-MoS2 modification for dual-peak detection

A graphene-MoS2-based dual-core D-shaped biosensor is proposed. The sensor operates in the terahertz (THz) band and detects analytes with refractive indices from 1.33 to 1.38, encompassing most biomolecules. The accuracy of the measurement results is improved by dual-peak detection. Through optimization, the thickness of graphene is 4 times of single-layer graphene, the thickness of MoS2 is 10 µm, the thickness of the analyte is 22 µm, and the diameter of the small air hole is 52 µm. The main and secondary peaks of the sensor showed high sensitivity of 632.606 µm/RIU and 374.609 µm/RIU, respectively. Meanwhile, both the main and secondary peaks have very high figures of merit (FOM), with the highest value of 21,162.16 and 63,809.01, respectively, reflecting the sensor's excellent sensing performance. The proposed sensor provides a new idea for studying the graphene-MoS2-based dual-core biosensor.