Simulation of a microstructure fiber pressure sensor based on lossy mode resonance

Abstract

We design and theoretically model a highly sensitive pressure sensor based on lossy mode resonance with a microstructure fiber. The microstructure fiber sensor is manufactured with an exposed-core photonics crystal fiber, on which a TiO2/HfO2/rubber polymer trilayer is coated. Using the sensitive film as a sensing channel avoids filling the air holes with liquid. Strong birefringence with x-polarized and y-polarized peaks is generated because of the asymmetric sensing region. The y-polarization has a higher coupling efficiency and the sensitivity of the y-polarized peak is higher than that of the x-polarization. An extremely high refractive index (RI) sensitivity 67 000 nm/RIU is obtained in the sensing range of 1.33-1.39. The TiO2/HfO2 bilayer film dramatically increases the pressure sensitivity of the sensor to a peak of 5.0μm/MPa, which is 2.5 times more sensitive than previously reported lossy mode resonance (LMR) sensors. In addition, the performance of the sensor is optimized by adjusting the type and thickness of the film. This paper provides a reference for developing a microstructure pressure sensor based on lossy mode resonance.