Fiber optic refractometer based in multimode interference effects (MMI) using Indium Tin Oxide (ITO) coating

In this paper we report the experimental results of a fiber optic refractometer based in multimodal interference effects (MMI) using an Indium Tin Oxide (ITO) coating. The MMI sensor is able to detect different liquid concentrations of glycerin and other substances. In addition, the use of ITO coating, deposited by the sputtering technique, allows a significant increment in the device sensitivity. In specific, we obtained a sensitivity around 297.12 nm/RIU for 18nm ITO coating thickness.