Silicon plasmonic integrated interferometer sensor for lab on chip applications

A sensing structure on a silicon platform is proposed with access silicon waveguide ports. The sensing mechanism is mainly based the interference effect between the SPP wave on both interferences. The sensing platform contains a metal channel deposited on silicon nitride base. The top and the bottom metal surfaces carry 2 decoupled SPP modes. The dimensions are optimized to maximize the coupling from the input silicon waveguide to the SPP wave at the top and bottom metal interfaces. High sensitivity and small foot print is achieved using this integrated simple plasmonic design. Full wave analysis is performed to examine the performance and optimize the dimensions and material. The optimized design and optimal material yield enhanced sensitivities of 19400 nm/RIU.