Temperature sensor based on multi-layer MoS2 coated etched fiber Bragg grating.

The development of an etched fiber Bragg grating (eFBG)-based temperature sensor with a uniform multi-layer molybdenum-di-sulphide (MoS2) coating is presented in this paper. Multi-layer MoS2 has been coated on clad etched FBG sensors by DC magnetron sputtering of molybdenum (Mo) and subsequent sulfurization. The dependence of temperature sensitivity on the coating thickness of MoS2 on eFBGs has been tested from room temperature to 100°C. It has been found that MoS2 coated clad etched FBG sensors with a coating thickness of around 10 nm exhibit a maximum temperature sensitivity of ∼95  pm/°C (almost one order higher than that of bare fiber Bragg gratings), with a resolution of ∼0.01°C obtained using an FBG interrogator with 1 pm resolution.