Pascal Bernage

TL;DR: A comprehensive survey of photosensitivity in silica glasses and optical fiber is reviewed in this article, where the mechanisms contributing to germanium or aluminum doped fiber photosensitivity are discussed within the framework of photoelastic densification models.

TL;DR: In this article, the authors used real time measurements of the spectral transmission, of the fwhm bandwidth and of the resonance wavelength of the Bragg gratings to estimate the refractive index change photoinduced in the core of the fiber.

TL;DR: In this paper, surface level modulations associated with the writing of the Bragg grating were investigated and it was shown that a densification takes place. And the corresponding peak to peak change of the refractive index to be 1.4−1.7 × 10−4 whether a pulsed or a CW irradiation mode is used.

TL;DR: In this paper, photo-induced Bragg reflectors at 1480 nm are written at both ends of the fiber amplifier and laser oscillation clamps the gain and suppresses low frequency signal or pump induced gain fluctuations.

TL;DR: Second order diffraction has been observed from Bragg gratings written within germanosilicate glass fibres as discussed by the authors, which is consistent with a saturation in the photo-induced change in refractive index.