A high-performance biosensor based on one-dimensional photonic crystal for the detection of cancer cells

In this study, we present a novel, highly sensitive, and compact one-dimensional (1D) binary photonic crystal biosensor designed for real-time detection of malignant cells, including breast, cervical, and basal cancer cells. It utilizes a GaAs/MgF₂ multilayer photonic crystal with a central defect layer, which creates a resonant peak within the photonic band gap. Introducing different cancerous cell samples into the defect layer causes a shift in the resonant mode position, which correlates with the refractive index changes of the samples. Using the transfer matrix method (TMM), we analyzed the spectral properties of the structure. We investigated the effects of incident angle, defect thickness, and the number of periods on the transmittance of TE waves. Additionally, this article investigated the performance comparison between TE and TM modes. To achieve the highest sensitivity in our design, we have discussed the procedure for optimizing the biosensor parameters. At these optimized conditions, the biosensor achieves a sensitivity of 2564.83 nm/RIU, a quality factor of 2979.317, and a figure of merit (FOM) of 3612.175 RIU⁻¹. To highlight the novelty of our work, we have compared our results with previous research in photonic biosensing, demonstrating significant improvements in sensitivity and performance.