Temperature-Insensitive Measurement of Refractive Index Using a No-Core Fiber-Based Modal Interferometer

We demonstrate a temperature-insensitive refractive index (RI) sensor based on an SMF-NCF-SMF structure-based modal interferometer with a wave configuration. The RI measurement sensitivity of our proposed refractometer was ∼-53.24nm/RIU with no temperature sensitivity (0 pm/°C).