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

Abstract

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.