Photonic crystal as a refractometric sensor operated in reflection mode

In this work, one dimensional ternary photonic crystal is investigated as refractometric sensor. Using Chebyshev polynomials of the second kind, the transmission of an incident wave from a ternary photonic crystal is studied in details. The variation of the transmissivity with the angle of incidence and wavelength of incident light for different values of number of periods is investigated. Water and air are assumed to be analyte layers. It is found that for water as an analyte, the peak angular shift is Δθ = 1.6° and the peak wavelength shift is Δλ = 2.6 nm for a change in the index of refraction Δn = 0.02. Moreover, the peak angular shift can reach up to Δθ = 7.05° for specific values of the layer thicknesses.