A diamond-shaped bio-sensor based on two-dimensional photonic crystal nano-ring resonator

In this paper, we demonstrated a diamond-shaped bio-sensor based on the nano-ring resonator using two-dimensional photonic crystal (2D-PhC). The biosensor is consisted of a ring resonator and two waveguides. The ring resonator with two end waveguides in both sides, are placed in middle of the structure. Due to the analyte binding to the sensing holes, the refractive index of holes is changed and consequently the resonant wavelength is shifted. According to the results, the resonant wavelength shift in the range of 1.33-1.55 is linear with respect to the refractive index variations. The quality factor and sensitivity of biosensor are respectively obtained about 2840 and 3.0 nm/fg.