摘要
利用光纤火焰熔融拉锥法,制作了一种高灵敏微光纤氨气(NH_3)传感器.该传感器将一段长度为10mm的保偏光纤接入普通单模光纤中,通过光纤火焰熔融拉锥机将保偏光纤熔融拉伸至直径为8.33μm制作而成.该结构基于马赫-曾德干涉仪的原理,利用保偏光纤纤芯模与包层模相互作用实现模间干涉.外界环境中NH_3浓度变化时,细锥区倏逝场发生变化,通过检测透射谱中波长的漂移,实现传感器对环境中NH_3浓度的测量.实验结果表明,当NH_3浓度由8ppm^56ppm变化时,透射谱向长波方向移动约5nm,且NH_3浓度与波长漂移成二次拟合.在NH_3浓度为32ppm^56ppm变化时,可将NH_3浓度与波长漂移近似看成线性关系,此时传感器的灵敏度为176.08pm/ppm.该传感器具有体积小,制作简单,灵敏度高等优点,可用于不同领域的NH_3传感测量.
A highly sensitive microfiber ammonia（NH3）sensor was fabricated by means of flame melting taper in this paper.The sensor is fabricated by splicing a length of 10 mm Polarization Maintaining Fiber（PMF）in the middle of ordinary Single Mode Fibers（SMF）,stretching the PMF down to microscale with diameter of 8.33μm by using optical fiber melt tapering machine.Based on the principle of MachZehnder Interferometer（MZI）,this structure utilizes the interaction of PMF core and cladding modes to achieve inter-mode interference.When the NH3 concentration changes in the external environment,the evanescent field in the cone area changes.By detecting the wavelength shift of the transmission spectrum,the concentration of ammonia can be measured by fabricated sensors in this paper.The experimental result shows that the sensor has a quadratic corelation to ammonia concentration in the range of 8 ppm-56 ppm,and the wavelength shift about 5 nm in the direction of the long wave.The experimental result also shows that the sensor has a linear corelation to ammonia concentration with sensitivity of 176.08 pm/ppm in the range of 32 ppm-56 ppm.The sensor has the advantages of small size,easy fabrication and high sensitivity making it a good candidate for NH3 sensor in different fields.
出处
《光子学报》
EI
CAS
CSCD
北大核心
2018年第3期170-175,共6页
Acta Photonica Sinica
基金
陕西省自然科学基础研究计划(No.2016JQ6021)
西安石油大学研究生创新与实践能力培养项目(No.YCS17111019)资助~~
关键词
微型光纤
马赫曾德干涉仪
氨气传感器
熔融拉锥
倏逝场
Microfiber
Mach- Zehnder interferometer
Ammonia sensor
Fused taper
Evanescent field
