A 1D photonic crystal-based sensor for detection of cancerous blood cells

In this work, we propose a novel compact bio-sensing platform based on defected photonic crystal waveguide for cancerous blood detection. The introduction of the defect layer in the middle of the structure leads to a sharp resonant peak in the photonic band gap of the transmittance spectrum. It is found using the Transfer Matrix Method that the resonant wavelength of the biosensor is red shifted on increasing the refractive index of the blood sample placed in the defect layer of the structure. The optimized thickness of the defect layer leading to well-defined, sharp and highly distinguishable resonant peaks is found to be 7 mu m. At this defect thickness, comparatively higher sensitivity and performance have been achieved. Our proposed structure exhibits a sensitivity of 244.4 nm/RIU and a quality factor as high as of 9138 for a refractive index of 1.392 at normal incidence. Furthermore, at the incidence angle ranges from 40 degrees to 60 degrees the sensitivity of the sensor improved from 291 to 344 nm/RIU. The structure has the potential to detect and sense cancerous blood samples with high efficacy.