Abstract
A dielectric superconductor binary photonic crystal (PC) is investigated as an optical sensor for detecting Escherichia coli (E. coli) bacteria. The structure of the proposed PC is (Si/superconductor)(N) (E. coli)/(Si/superconductor)(N). Four different high critical temperature superconductors are employed in the structure. These superconducting materials have temperature- and frequency-dependent refractive indices. Transmission spectra of the PC are investigated and the sensitivity to E. coli bacteria is found to be 165.735 nm/RIU. The sensitivity dependences on the thickness of the defect layer and superconductor material, operating temperature and angle of incidence are investigated. The sensitivity, figure of merit and quality factor are 296.754 nm/RIU, 27936.5 RIU-1 and 66913, respectively, when optimum values of these parameters are employed. It is also found that the superconductor Bi2Sr2Ca2Cu3O10, which has the lowest London penetration length, corresponds to the highest sensitivity.