基于熔融拉锥型光子晶体光纤（PCF）的马赫-曾德尔(M-Z)干涉仪是在一段实芯PCF两端分别熔接单模光纤后进行熔融拉锥制作而成的，该传感器透射光谱的干涉条纹对比度可达2.23 dB。利用该传感器实现了对不同质量浓度氯化钠溶液传输光谱的检测，研究了其传输光谱与外界折射率的响应关系。实验结果表明，在折射率变化范围为1.333~1.349时，该传感器对于不同质量浓度氯化钠溶液的折射率测量灵敏度为210.075 nm/RIU；在温度测量范围为20 ℃~70 ℃时，其温度灵敏度约为0.0018 nm/℃，在测量中能够克服温度交叉敏感问题。

Based on the fused tapered photonic crystal fiber (PCF), a Mach-Zehnder interferometer is proposed. The both ends of PCF is joined in a splice with a single-mode fiber and the interference fringe contrast of the transmission spectra is 2.23 dB. The transmission spectra of sodium chloride solutions with different mass concentrations are obtained. The corresponding relationships between the transmission spectra and external refractive index are analyzed. The experimental results show that the refractive index sensitivity of the sensor is 210.075 nm/RIU in the index range of 1.333~1.349, by measuring different mass concentrations of the sodium chloride solutions. In the temperature range of 20 ℃~70 ℃, the temperature sensitivity is about 0.0018 nm/℃ . This sensor is able to overcome the problem of cross sensitivity of temperature in the measurement.