Grating-coupled 1D photonic crystal biosensor for glucose sensing

In this paper, the implementation of a wavelength-controlled Bloch surface wave device structure for glucose detection is studied. The impedance matching method is used as a guide to optimize the biosensor. Incident light enters the structure, coupled to a photonic crystal via a grating, and Bloch surface wave modes can be identified and localized in the vicinity of the grating. Optimizing the quality factor of the Bloch surface wave modes is achieved by modifying the thickness of the buffer layer, the number of period layers in a photonic crystal, and the incidence angle. Theoretical investigations indicate that these system parameters can enhance the sensing performance of biosensors. Combining the highly quality factor of resonance peak and the large wavelength sensitivity, the figure of merit of the biosensor can reach as high as 642.8(𝑔 ⁄ 𝑚<i>l</i>)⁻¹. These results can help the design of biosensors for the detection of Glucose with high-performance.