Design of an Integrated Optics Sensor Structure Based on Diamond Waveguide for Hemoglobin Property Detection

This manuscript presents a theoretical analysis of a diamond-based integrated optics structure for applications in biosensors. The geometrical, optical, and sensitivity properties of an integrated optical structure were theoretically analyzed and optimized for biosensor applications. The analysis focused on determining the waveguide properties, including the effective refractive index N(eff) as a function of refractive index n(w) and thickness d(w) of waveguide layer, refractive index of the hemoglobin cover layer n(cH) and substrate layer n(s), homogeneous sensitivity dN(eff)/dn(cH), and modal field distribution of guided waveguide modes. The analysis was completed for two types of waveguide layer materials: undoped or boron-doped diamond films with or without the hemoglobin cover layer. The presented experimental results form a base for developing biosensor structures based on integrated optics for determining the properties of hemoglobin.