Bragg gratings were fabricated in an Sn–Er–Ge-codoped silica fiber with a phase mask and ultraviolet radiation from a 248-nm KrF excimer laser. The photosensitivity of the fiber was examined by studying the initial growth rate of the gratings written into it. The thermal stability of the gratings was investigated and modeled in terms of both the refractive-index modulation and the effective refractive index of the fiber core. It was shown that the temperature-induced irreversible shift in the Bragg wavelength could not be predicted by the isothermal decay of the refractive-index modulation. Finally, the potential of the gratings written into the fiber is discussed in terms of their use in high-temperature-sensing applications.
© 2004 Optical Society of America
(060.0060) Fiber optics and optical communications : Fiber optics and optical communications
(060.2310) Fiber optics and optical communications : Fiber optics
(060.2370) Fiber optics and optical communications : Fiber optics sensors
(120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
(120.6780) Instrumentation, measurement, and metrology : Temperature
Suchandan Pal, Tong Sun, Kenneth T. V. Grattan, Scott A. Wade, Stephen F. Collins, Gregory W. Baxter, Bernard Dussardier, and Gérard Monnom, "Bragg gratings written in Sn–Er–Ge-codoped silica fiber: investigation of photosensitivity, thermal stability, and sensing potential," J. Opt. Soc. Am. A 21, 1503-1511 (2004)