Simulation design of a subwavelength Fano-photonic ring resonator pressure sensor based on Finite Element Method

A subwavelength Fano-photonic ring resonator pressure sensor is designed in this paper using Finite Element Method (FEM) and Finite Difference Time Domain (FDTD). The sensor is consisted of a PMMA photonic ring waveguide which can produce resonance spectrum to realize pressure measurement. But research shows that the resonance depth is attenuating with the increase of spectral wavelength. So a Fabry-Perot (FP) structure is introduced to the sensor to produce Fano-line shapes. The interaction between the strong trapped resonance of the FP resonator and the weak resonance of the ring resonator can improve the resonance depth to ensure measurement accuracy. After structural optimization, this sensor can realize the pressure sensitivity of 6.49286 nm/MPa and the low temperature cross-sensitivity of 0.00208 nm/°C. This pressure sensor is based on integrated photonics and has broad application prospect in pressure sensor array.