Bacterial Detection in Contaminated Water Using a Photonic Crystal Sensor

This research proposes the design of an optical sensor that may be used to identify the presence of bacteria in contaminated water. We have taken a 2D photonic crystal structure into consideration for the design of the proposed sensor. An MIT-MEEP simulation tool is used to analyse the sensor. Studying the optical characteristics of various bacteria in water allows us to provide the refractive index value as an input to MEEP. Different bacteria's final responses to the proposed structure are analysed. The photonic crystal's refractive index profile changes when bacteria's refractive index varies. Because of the variation in bacteria's refractive index, the central frequency and wavelength are affected. The change in refractive index can be picked up by recording changes in the wavelength and frequency of the light transmitting through the structure. The analysis of the transmission and reflection spectra is made by using the MIT Electromagnetic Equation Propagation (MEEP) simulation tool. As bacteria's refractive index changes, it is shown that the wavelength and frequency shifts are significant.