基于二模-单模微纳光纤Sagnac环的高灵敏度光纤温度传感器

Highly Sensitive Fiber Optic Temperature Sensor Based on Two-Mode-Single-Mode Microfiber Sagnac Loop

提出并研究了一种基于二模-单模光纤复合型微纳光纤Sagnac环(TS-MSL)的高灵敏度光纤温度传感器。TSMSL采用两段单模光纤中间熔接一段二模光纤并经熔融拉锥制备而成,基于聚二甲基硅氧烷(PDMS)材料进行封装。实验结果表明,TS-MSL的光场干涉增强效应结合PDMS材料的光热敏感特性,有效提升了微纳光纤的温度感知能力,实现了高灵敏度温度传感。相比于普通单模微纳光纤Sagnac环,该光纤传感器的温度灵敏度提升了120倍,高达8.13 nm/℃。该传感器具有较高的灵敏度,在有毒气体和腐蚀环境等特殊场合的精确温度监测中有较大的实用价值。

We propose and investigate a highly sensitive fiber optic temperature sensor based on a two-mode-single-mode microfiber Sagnac loop(TS-MSL).The TS-MSL is fabricated by fused biconical tapering after a section of two-mode optical fiber is spliced between two sections of single-mode optical fibers,and it is packaged by the polydimethylsiloxane(PDMS)material.The experimental results reveal that the temperature sensing performance of the proposed sensor is effectively improved due to the optical field interference enhancement of TS-MSL as well as the photothermal sensitivity of the PDMS material.The temperature sensitivity of the proposed fiber sensor is up to 8.13 nm/℃,which is about 120 times higher than that of the ordinary single-mode microfiber Sagnac loop.With high sensitivity,the proposed temperature sensor is of high practical significance for accurate temperature monitoring in special occasions such as toxic gases and corrosive environments.