Double-Groove ZnO-Au Photonic Quasi-Crystal Fiber Surface Plasmon Resonance Sensor

A photonic quasi-crystal fiber surface plasmon resonance (PQF-SPR) sensor composed of a ZnO-Au bilayer film is designed and analyzed. Finite element analysis is performed to analyze the influence of the groove structure on the sensing properties. The results reveal that the shape of the groove directly influences the coupling between the core mode and the surface plasmon polariton (SPP) mode as well as the peak loss and full-width at half-maximum (FWHM) of the loss spectra. By optimizing the groove shape and structural parameters of the PQF, a maximum wavelength sensitivity of 25,000 nm/RIU and a quality factor (figure of merit) of 432 are attained in the refractive index range between 1.30 and 1.41. This study provides valuable insights and guidance for the development and optimization of high-performance SPR sensors.