Thermal Stability of Drawing-Tower Grating Written in a Single Mode Fiber

The thermal stability of drawing-tower grating (DTG) has become the primary concern in applications because of its great advantages in building a large-capacity distributed fiber grating sensing network. Different aging trainings were performed on the DTGs written by single laser pulses at 193 nm in a low-germanium doped silica fiber, and the thermal stability of Bragg wavelength and reflectivity at different temperatures were investigated to demonstrate that the DTG is reliable in some sensing applications. A double exponential function model is proposed as a method to study the decay characteristics of the DTG reflectivity.