Towards Sensing Performance of Metal Clad Planar Waveguide Sensor with Transition Metal Dichalcogenide Materials

Abstract

The sensing performance of liquid filled prism coupled standard metal clad planar waveguide sensors in presence of transition metal dichalcogenide materials are studied and compared with similar polymer waveguides. For comparison point of view, the film thickness of SiO2 waveguide and polymer waveguides is so chosen that they have same effective refractive index. The modal equation and other necessary formulae of proposed waveguides are derived using boundary matching technique. Our analysis shows that the sensing performances of both waveguides are improved in presence of an adlayer of transition metal dichalcogenide material. In our all considered 2D materials, monolayer of WS2 material shows maximum sensitivity and quality parameter for SiO2 waveguide and WSe2 material shows maximum sensitivity and quality parameter for polystyrene waveguide. Hence, Tungsten based 2D materials always give better sensing performance than the Molybdenum based 2D material in our all considered cases. Also, the analysis shows that the sensing performance of SiO2 guiding layer waveguide is better than the polymer guiding layer waveguide. The obtain maximum sensitivity and quality parameter of our proposed SiO2 waveguide in presence of WS2 material is 4410/RIU and 2138/RIU, respectively.