Enhanced strain and temperature sensing by reduced graphene oxide coated etched fiber Bragg gratings

This Letter reports on an etched fiber Bragg grating (eFBG) sensor coated with reduced graphene oxide (RGO) having enhanced sensitivity for physical parameters such as strain and temperature. The synergetic effect of the changes in grating pitch and refractive index of RGO with change in temperature or strain enhances the shift in Bragg wavelength (lambda(B)). The RGO-coated eFBG sensors exhibit a strain sensitivity of 5.5 pm/mu epsilon (similar to 5 times that of bare fiber Bragg gratings) and temperature sensitivity of 33 pm/degrees C (similar to 3 times that of bare fiber Bragg gratings). The resolutions of similar to 1 mu epsilon and similar to 0.3 degrees C have been obtained for strain and temperature respectively, using RGO-coated eFBG sensors. (C) 2016 Optical Society of America