A novel biosensor based on a coupled surface plasmon nanostructure

摘要

A novel plasmonic biosensor based on coupled metal-dielectric buffer grating is proposed and analyzed by the rigorous coupled wave analysis (RCWA) method. The metal-dielectric buffer grating structure offers surface plasmon resonance suitable for high sensitivity biosensing applications. The calculated FWHW (full width at half maximum) of the transmission peak is 5 nm and the optical transmission efficiency is significantly enhanced at the resonant wavelength of 800.8 nm by introducing the dielectric buffer grating. The highly concentrated field distribution is sensitive to surrounding refractive index changes of the metal surface providing a sensitivity of 560 nm/RIU (refractive index unit) for optical biosensing applications.