Slot Waveguide with Grating Based Cladding for Protein Detection

We demonstrate slot waveguide with grating based biosensor in aqueous analyte for protein detection. A slot waveguide is formed between the cladding by silicon and TiO2 in form of grating structure where the resonant optical mode is confined in a low index region. This proposed device numerically detects hemoglobin, globulin and BSA protein in aqueous analyte, with high sensitivity of 600 nm/RIU, FOM (Figure of merit) of 300 and high Q factor of 9650 compared to the conventional slot waveguide.