One dimensional multilayer structure for kerosene adulteration detection in petrol and diesel

We aim to design a multilayer periodic structure to detect the kerosene adulteration in the petrol and diesel fuels on a single processing setup. We built the structure by arranging TiO2 and SiO2 layers periodically in alternate manner with empty space at the middle. The optical response of the designed structure is then theoretically studied using transfer matrix method. Empty space of the design is filled with different kerosene adulterated petrol and diesel samples for inspecting structure response to incident electromagnetic waves. Theoretical calculations affirm that the proposed structure is capable to detect the fuel adulteration efficiently. Critical performance parameters like sensitivity, quality factor, figure of merit and limit of detection are calculated to check the effectiveness of the sensor. We also optimized the sensitivity of sensors design through modifying the defect thickness as well as angle of incidence of electromagnetic waves, and provides poly fit formula. It is observed that the sensitivity of sensor to detect kerosene adulteration in fuels highly depends on defect thickness and light incidence angle. An efficient sensor possessing high quality factor and figure of merit is realized from the designed structure that is capable of detecting 10-5 RIU.