Design analysis of one-dimensional photonic crystal based structure for hemoglobin concentration measurement

In this manuscript, a porous one-dimensional Photonic Crystal (1D-PhC) based sensor is designed for bio-chemical sensing application (i.e., hemoglobin concentration). The alternate layers of silicon are considered for design optimization, where the porosity is introduced to obtain the desired index contrast value. The sensing capability of the proposed design is enhanced by modifying the dispersion property of the structure. For this, a defect middle layer is deliberately introduced. The number of layers, defect layer optical thickness, and porosity values are optimized to confine a defect mode of desired wavelength. Finally, the detailed analysis of proposed structure is carried out. This provides the average sensitivity of around 323 nm/RIU (0.05 nm/(g/L) along with considerably higher Figure-of-merit (FOM) of 517 RIU⁻¹.