Sensing blood components and cancer cells with photonic crystal resonator biosensor

This study presents the design and numerical analysis of an optical biosensor utilizing a photonic crystal resonator to detect alterations in the refractive index in human blood. The biosensor has potential applications for early diagnosis of cancer cells and various viruses. The structure of the biosensor being proposed is comprised of a waveguide and an oval ring resonator, designed via silicon rods in a 2D square lattice. Accurate detection can lead to choosing the best therapeutic approach and accelerate the patient's recovery, which is possible by utilizing this biosensor. An optimized and compact design of biosensor (10.2 mu m x 7.5 mu m) with a significant detection resolution and detection limit of (1*10)(-4), a wide range of cell and virus detection from a refractive index of (1.330 similar to 1.401) proposed to be implemented in real-time medical applications The proposed sensor has a good figure of merit, and high sensitivity values ranging between 650 and 900. Accordingly, an improved sensor with a quality factor as high as 190 is achieved. Through the implementation of the finite-difference time-domain (FDTD) method, the resonator's reaction to perturbations induced by cells and viruses present in the blood is investigated. The exceptional characteristics of biosensor make it one of the potential candidates in the field of biomedical sensing, which exhibits better sensitivity at the Terahertz band, compared to prior works.