Abstract:
In recent years, various devices based on Photonic Crystal material are designed and
fabricated such as Multiplexers, Filters and Sensors etc. Optical Sensors based on a Photonic principle have also a wide range of applications in the field of health care, defense, security, automotive, aerospace, environment and food quality control.
Photonic crystals with one-and two-dimensional have been studied for a variety of refractive index sensing applications. In this work, we propose a new design principle of two-dimensional photonic crystal (PC) refractive index sensors with high transmission and sensitivity simultaneously. The proposed sensor is made of two waveguide couplers and one microcavity which is obtained by varying the radius of one air hole in the center of PC structure. The microcavity is separated from the input and output waveguides by many holes of the PC. It is shown that by injecting an analyte such as gas or a liquid into a sensing hole, and thus changing its refractive index, a shift in the resonant wavelength may occur. The transmission spectra, quality factor and sensitivity of the sensor have been analyzed numerically through the finite
difference time domain (FDTD) method. The sensitivity value of the sensor has been found to be 668 nm/RIU with minimum detection limit of 0.0002 RIU, which proves the ability of the structure to produce biosensor PC
