This Letter demonstrates a refractometer in integrated optical fiber, a new optical platform that planarizes fiber using flame hydrolysis deposition (FHD). The unique advantage of the technology is survivability in harsh environments. The platform is mechanically robust, and can survive elevated temperatures approaching 1000°C and exposure to common solvents, including acetone, gasoline, and methanol. For the demonstrated refractometer, fabrication was achieved through wet etching an SMF-28 fiber to a diameter of 8 μm before FHD planarization. An external refractive index was monitored using fiber Bragg gratings (FBGs), written into the core of the planarized fiber. A direct comparison to alternative FBG refractometers is made, for which the developed platform is shown to have comparable sensitivity, with the added advantage of survivability in harsh environments.

中文翻译：

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平面光纤中的van逝场折光法

这封信演示了集成光纤中的折光仪，这是一种新的光学平台，可以通过火焰水解沉积（FHD）使光纤平面化。该技术的独特优势是在恶劣环境下的生存能力。该平台机械坚固，可承受接近1000°C的高温并暴露于普通溶剂（包括丙酮，汽油和甲醇）中。对于演示的折光仪，通过在FHD平面化之前将SMF-28纤维湿法刻蚀成直径为8μm的光纤来完成制造。使用光纤布拉格光栅（FBG）监测外部折射率，该光栅被写入平面化光纤的纤芯中。直接与替代的FBG折光仪进行了比较，结果表明，开发的平台具有可比的灵敏度，