This paper shows that two annealing processes must be considered when predicting the effect of temperature on fibre Bragg gratings that have been written by UV radiation in boron/germania co-doped fibres. Both the thermal decay of the grating-related refractive index and the annealing of the boron-induced refractive index contribute to the wavelength shift observed. We have combined the theory of these two effects to match data taken experimentally (accuracy ±0.3 nm) and successfully explained a selection of observed wavelength shifts ranging from -2.83 to +0.75 nm.
- condensed matter
- electric, magnetic and optical optics
- quantum optics and lasers