Multiplexed fiber-optic Fabry-Pérot cavities for refractive index and temperature sensing fabricated using diamond-blade dicing

We report on multiplexing several Fabry-Pérot (FP) cavities in single-mode optical fibers for highprecision spatially resolved sensing of refractive indices (RI) liquids. Resonators are fabricated by cutting small slots into using a diamond-blade dicing saw and additional coating with thin Ta 2 O 5 layers to increase cavity reflectance. Temperature compensation RI measurements is achieved either evaluating the reflection signals resulting from solid core parts between different open-cavity sensor elements, or Si inlay glued one open cavities. The performance accuracy sensors up four were tested sucrose solutions over range temperatures.