Control over the resonance wavelength of fibre Bragg gratings using resistive coatings based on single-wall carbon nanotubes

We demonstrate that a thin resistive coating based on single-wall carbon nanotubes applied to the lateral surface of an optical fibre allows it to be uniformly heated up to a temperature of ~400 °C without damage to the coating. Using a fibre Bragg grating (FBG) as an example, we assess the efficiency of resonance wavelength thermal tuning and examine frequency characteristics that can be achieved using such coating. In particular, we show that the resonance wavelength of the FBG can be tuned over 3.2 nm with an efficiency of 8.7 nm W^-1 and time constant of ~0.4 s.