Influence of single-walled carbon nanotubes cladding on reflectivity of uniform fiber Bragg grating

The influence of single-walled carbon nanotubes (CNTs) cladding on reflectivity of uniform fiber Bragg grating (FBG) is experimentally studied. The FBG is coated with single-walled carbon nanotubes. Initially, the single-walled carbon nanotubes cladding worked as light amplitude limiting effect on the FBG. So the reflectivity of the FBG decreased. After FBG exposed in air for a few days, the reflectivity of the CNT-FBG is gradually increased. Finally, the reflectivity of the CNT-FBG is larger than that of the original FBG. Within these periods, the center wavelengths of FBG have nearly no drifted. This phenomenon is analyzed by the simulation method with anisotropy material cladding theory. The theoretical and experimental results agree with each other very well.