Optimization of the geometries of Palladium-Coated Single Mode Tapered Fiber Hydrogen Sensors for improving sensitivity

摘要

We have proposed an experimental study on the effect of the fiber profile parameters on the sensitivity of the tapered optical fiber hydrogen sensors. To study the effects of taper profiles on the sensitivity of the tapered fiber, we divided our study into three experiments where the main parameters of each experiment are tapering angle, waist diameter, and taper length. To examine the effects of taper profile on the sensitivity of tapered fiber, we fabricated eight tapered fibers with varying taper profile. By controlling the fabrication conditions such as pulling duration, pulling speed, heating length, and temperature, tapered fiber with different shapes and properties can be fabricated. By measuring and comparing the sensitivity of the fibers, we found that tapering angle, waist, and length have a significant effect on the sensitivity of the sensor. According to the first part of our experiments, the sensitivity increases from 2.5% to 7% when the angle was increased from 2° to 4°. The second part of our experiments shows that the sensitivity increases from 7% to 8.5% when the length was increased from 10mm to 20mm. The last part of our experiments shows that the sensitivity increases from 4% to 5.5% when the waist diameter was decreased from 35μm to 15μm. To ensure which parameter is being studied, we fixed all other parameters in our experiments. The results of this research show that increasing the tapering angle and length can both help improve sensitivity. Decreasing the waist diameter can also improve sensitivity. We believe that the tapering angle has the most significant effect on the sensitivity of the sensor.