Photonic Crystal Based Bio-Sensor using Rhombic Ring Resonator for Cancer Cell Detection

In this paper, a 2D photonic crystal based biosensor using rhombic ring resonator is proposed and formulated for cancer cell detection. Sensor is designed by creating holes in two dimensional photonic crystal silicon slab with hexagonal lattice and rhombic ring resonator structure is created by having bi-periodicity in the silicon slab. The sensing mechanism of rhombic ring resonator is dependent on the refractive index of the analyte used thereby it is possible to detect cancer cells based on their refractive indices. As the refractive index of normal cell and cancer cell differs the corresponding linear change in wavelength shift is observed. Simulation on the proposed structure and the analysis of the results are centered on Finite Difference Time Domain (FDTD) method. And for designing the sensor structure and analyzing sensor output Lumerical software tool has been used. The proposed sensor is sensitive to even a small change in refractive index and can differentiate between normal cell and cancerous cell. For the proposed sensor resonating wavelength is about 1547nm and Q (quality) factor of 5953 is achieved with sensitivity of 104nm/RIU.