A Mach–Zehnder interferometer sensor based on tapered no-core fiber (NCF) is proposed in this paper. Due to the multimode interference of the single-mode fiber (SMF)–NCF–SMF structure and the higher-order modes excited by the tapered structure, the sensor is more sensitive to the refractive index. The refractive index sensitivities are 130.5 nm RIU⁻¹ from 1.340 to 1.380, 330.0 nm RIU⁻¹ from 1.380 to 1.420, and 906.0 nm RIU⁻¹ from 1.420 to 1.440, respectively. The temperature sensitivity is 0.0595 nm C⁻¹ from 30 C to 90 C. This proposed sensor has a simple structure and low cost, which can be widely used for biological sensing.

本文提出了一种基于锥形无芯光纤（NCF）的Mach-Zehnder干涉仪传感器。由于单模光纤（SMF）–NCF–SMF结构的多模干涉以及锥形结构激发的高阶模，传感器对折射率更加敏感。折射率灵敏度分别为从1.340至1.380的130.5 nm RIU ^-1，从1.380至1.420的330.0 nm RIU ^-1和从1.420至1.440的906.0 nm RIU ^-1。从30摄氏度到90摄氏度，温度灵敏度为0.0595 nm C ^-1。该传感器结构简单，成本低廉，可广泛用于生物传感。