Design and analysis of optical ring resonator for bio-sensing application

In this work, a ring resonator is designed and analyzed for the spectral properties. A ring and a bus waveguide is designed with a core width of 0.2μm and cladding width of 2μm respectively. The bus waveguide is designed with a height of 14.4μ, width of 2μm and a layer thickness of 900nm is considered. The structure is simulated with a wavelength of 1.55μm. The core refractive index of 2.5 and the cladding refractive index of 1.5 is considered in the design. The separation between the ring and bus waveguide considered in the design is 0.72μm. A perfect electric conductor is considered at the boundaries of the ring and the bus waveguide. The meshing of the structure is done, which involves the finite element method (FEM). The power at the input port is given as 1W. The coupling of the light in the core of the bus and ring waveguide is observed. Which will give a better limit of detection, and is required for biosensor. An increase in the transmittance is observed by reducing the radius of the ring, various ring circumference is considered for the analysis. A small ring structure is taken for consideration, as the smaller ring will be useful in the bio-sensing application, which can further be fabricated for a point of care devices.