We present a temperature‐sensitive, single‐mode–multimode–single‐mode (SMS) fiber structure with an index‐matching gel as a cladding material in a multimode segment. A silica core with the surrounding gel is supported straight by a thin glass tube to produce a bandpass transmission response. The passband wavelength shifts by 96 nm from 1624.5 to 1528.5 nm as the temperature increased from 40 to 200°C. The maximum sensitivity obtained is 2 nm/°C in the temperature range 40–70°C, whereas the minimum sensitivity is 0.13 nm/°C in the temperature range 125–200°C. The SMS fiber structure, including the gel cladding, allows high operating temperatures and high thermal sensitivities.

中文翻译：

---

基于带有凝胶包层的多模干涉光纤结构的高灵敏度温度传感器

我们提出了一种温度敏感的单模多模单模（SMS）光纤结构，其中折射率匹配的凝胶作为多模段中的包层材料。带有周围凝胶的硅胶芯被细玻璃管直接支撑，以产生带通传输响应。随着温度从40°C升高至200°C，通带波长从1624.5 nm移至1528.5 nm，偏移量为96 nm。在40–70°C的温度范围内获得的最大灵敏度为2 nm /°C，而在125–200°C的温度范围内获得的最小灵敏度为0.13 nm /°C。SMS纤维结构（包括凝胶包层）允许较高的工作温度和较高的热敏性。