▎ 摘　　要

In this letter, a highly sensitive refractive index biosensor applicable in medical devices is proposed. The biosensor design is analyzed for different concentrations of hemoglobin biomolecules. The 70nm shift in the wavelength is observed for two hemoglobin biomolecules with 1.34 and 1.36 refractive index per unit (RIU). The highest sensitivity of 3500 nm/RIU is observed for these hemoglobin biomolecules. The results are analyzed for absorption, electric field and magnetic field. The design is also analyzed for different geometrical parameters like metasurface array thickness and silicon dioxide (SiO2) layer thickness. The increase in metasurface array thickness reduces the absorption of the design. The increase in the thickness of SiO2 layer increases the absorption till 0.6 mu m thickness than the response remains the same for other thicknesses. The proposed highly sensitive graphene-based metasurface array biosensor is applicable in medical and biosensing photovoltaic devices.