Highly sensitive MoS2/graphene based D-shaped optical fiber SPR refractive index sensor with Ag/Au grated structure

Fiber optic surface plasmon resonance (SPR) sensors are widely used in sensing applications in the fields of physics, chemistry and biology. This paper presents a numerical simulation of a D-shaped fiber optic SPR based refractive index sensor designed with a silver, gold, molybdenum disulfide, and graphene coated structure with and without gratings, for the first time. A FEM-based software is used to carry out the simulation studies. Aiming to obtain the highest performance, gold/silver layers are coated with MoS2 and graphene. Sensor parameters are computed and optimum values are discovered for these parameters; grating periods, gap size between gratings, residual cladding thickness, gratings numbers, and thickness of coating layers. 11,775 nm /RIU as the maximum sensitivity in the range of 1.33-1.4 RI is reached. Results demonstrate that the proposed multilayer and grated structure yields a 98.7% higher sensitivity value with reference to the simulation of a regular D-shaped Ag-coated fiber SPR sensor, which makes it promising for chemical, biochemical, and other applications of the future with the delicate sensing ability.

Automated summary

This study presents a numerical simulation of a D-shaped fiber optic SPR sensor with a multilayer coated structure, which demonstrates higher sensitivity and superior performance compared to traditional SPR sensors. The proposed sensor has great potential for applications in the fields of chemistry, biochemistry, and other related areas.