TaSe₂/Graphene Biosensor Based on LRSPR Effect With Enhanced Sensitivity and FOM in Near Infrared Region

Few-layer transition metal disulfides have attracted much attention in the field of optoelectronic devices due to their unique optical and electronic properties. Among them, 2-D tantalum diselenide (TaSe2) nanocrystals have excellent flexibility, fast optical response properties, outstanding chemical stability, and light absorption properties, and thus have potential applications in the field of optical sensors. Here, we present for the first time an optical biosensor based on multilayer 2H-phase TaSe2/graphene, which can respond to subtle refractive index changes of the sensing medium by precise tuning of the optical and structural parameters of the sensor. The results of theoretical scientific studies show that multilayer TaSe2/graphene films at the nanoscale can produce extremely strong long-range surface plasmon resonance (LRSPR) in the sensor structure proposed in this article. Compared with the conventional Au nanofilm surface plasmon resonance (SPR) sensor, the figure of merit (FOM) of the proposed TaSe2 SPR-based sensor improved by a factor of 9.6. Our theoretical study demonstrates that TaSe2 is a surface plasmonic material with excellent performance and provides a theoretical reference for its experimental study in the field of biosensors.