Temperature-Insensitive Gas Pressure Sensor Based on Photonic Crystal Fiber Interferometer

Abstract

A temperature-insensitive gas pressure sensor was proposed and experimentally investigated. This sensor was based on a photonic crystal fiber sandwiched between two single-mode fibers, where the impact of length on the performance of the sensor has been studied. Air holes of photonic crystal fiber were employed as gas or liquid inlet and outlet channel which provide the medium for direct interaction between the light transmitted in the fiber and the target gases. The experimental results show that the length of photonic crystal fiber has little effect on the sensitivity to gas pressure. The photonic crystal fiber interferometer has a high gas pressure sensitivity of 2.39 nm/MPa when gas pressure increases from 100 KPa to 900 KPa. The demonstrated gas pressure sensor has excellent stability and reversibility with negligible temperature cross-sensitivity. The proposed photonic crystal fiber interferometer can also be used for liquid sample detection with high refractive index (RI) sensitivity of 3026 nm/RIU when the length of photonic crystal fiber is 1 cm at a RI range of 1.334-1.34. Therefore, the proposed photonic crystal fiber interferometer holds a great potential in applications for chemical gas leakage detection and biochemical sensing.