Resurgent regenerated fiber bragg gratings and thermal annealing techniques for ultra-high temperature sensing beyond 1400 degrees C

Abstract

We report for the first time the resurgence of regenerated fiber Bragg gratings (RFBGs) useful for ultra-high temperature measurements exceeding 1400 degrees C. A detailed study of the dynamics associated with grating regeneration in six-hole microstructured optical fibers (SHMOFs) and single mode fibers (SMFs) was conducted. Rapid heating and rapid cooling techniques appeared to have a significant impact on the thermal sustainability of the RFBGs in both types of optical fibers reaching temperature regimes exceeding 1400 degrees C. The presence of air holes sheds new light in understanding the thermal response of RFBGs and the stresses associated with them, which governs the variation in the Bragg wavelength.