Sensitivity enhancement of in-line chemical sensing device with C-type fiber and photonic crystal fiber

The in-line chemical sensing device with novel C-type fiber and photonic crystal fiber was successfully fabricated. We further improved the sensitivity or light coupling efficiency of our in-line chemical sensing device with optimized the Ctype fiber length. The results show that sensitivity and response time of device are significantly enhanced with optimization of cleaving and splicing process. The gas sensing experiments with the optimized conditions are demonstrated for detecting partial pressure of acetylene. We also numerically analyzed the sensitivity of ring-core defect photonic crystal fiber which was used in this experiment, through full-vectorial finite element method.