Growth Characteristics of Fiber Bragg Gratings Fabricated in High Germania Boron Co-Doped Fiber

• Main Author: S. W. Harun , P. Poopalan and H. Ahmad
• Format: Article
• Language: English
• Published: IIUM Press, International Islamic University Malaysia 2012-09-01
• Series: International Islamic University Malaysia Engineering Journal
• Online Access: http://journals.iium.edu.my/ejournal/index.php/iiumej/article/view/365

This paper reports and provides an explanation for the growth characteristics of fibre Bragg gratings (FBGs) fabricated  in high germania boron co-doped optical fiber by using a continuous wave (CW) doubled frequency Argon ion laser as an UV light source. The grating reflectivity and Bragg wavelength shift as a function of exposure time are measured. The index modulation time is observed to have a good fit to a power law of the form n = Ctb (t is the time, C and b are constants), whereas the exponent b of 0.3 is obtained for the FBGs. The UV laser light also causes a shift of the resonant wavelength with fabrication time. The fastest wavelength shift is shown to be 0.53 nm after 524 seconds exposure. Keywords: Fiber Bragg grating, Argon ion laser, Phase mask method, Growth characteristics.