Design of blood plasma concentrations sensor based on a one-dimensional photonic crystal

Abstract This study uses the transfer matrix method to calculate the transmittance spectrum of a one-dimensional photonic crystal (1D-PC). Herein, the crystal is composed of alternating layers of barium titanate ferroelectric and yttrium oxide dielectric. The spatial periodicity of the 1D-PC is broken by a cavity surrounded by thin layers of a critical high-temperature superconductor, which can be used to detect refractive index changes of plasma cells infiltrated into the cavity. The results reflect the existence of a maximum transmittance peak in the telecom region known as a localized mode within the photonic band gap. This study reveals that the localized mode shifts toward longer wavelengths as the operating temperature of the superconductor increases. Additionally, we calculate the sensitivity and quality factor of the localized mode, thereby finding that these quantities increase as the incidence angle increases. The proposed model works in cryogenic temperature environments and may be integrated into biosensor designs.