Compared to the multimode interference (MMI) effect, the anti-resonance (AR) effect does not rely on the multimode property of the optical waveguide. This Letter shows that fiber bending can suppress the MMI and can break the superposition of AR spectra of multiple modes in a high-index polymer-coated optical fiber interferometer based on a single-mode fiber—polymer-coated no-core fiber—single-mode fiber hetero-structure. This results in the dominance of the AR spectrum of an individual mode and consequently in periodic sharp transmission dips. As a result of this phenomenon and large thermo-optical and thermal expansion coefficients of the polymer, a compact, high-sensitivity and linear response temperature sensor with the sensitivity as high as ${-}{3.784}\;{\rm{nm}}/^\circ {\rm{C}}$ has been demonstrated experimentally.

中文翻译：

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高折射率聚合物涂层光纤干涉仪中基于反共振的高灵敏度温度传感器

与多模干扰（MMI）效应相比，反谐振（AR）效应不依赖于光波导的多模特性。这封信表明，在基于单模光纤—聚合物涂覆的无芯光纤—单芯光纤的高折射率聚合物涂覆的光纤干涉仪中，光纤弯曲可以抑制MMI，并且可以破坏多模的AR光谱的叠加。模光纤异质结构。这导致单个模式的AR频谱占优势，并因此导致周期性的陡峭的传输骤降。由于这种现象以及聚合物的大的热光学和热膨胀系数，因此，紧凑，高灵敏度和线性响应的温度传感器的灵敏度高达$ {-} {3.784} \; {\ rm {nm }} / ^ \ circ {\ rm {C}} $ 已经通过实验证明。