Authors : Aia T. Yhia, Tahreer S. Mansour and Yousif I. Hammadi
Abstract: This study presents a continuously tunable optical notch filter based on homodyne Machzehnder interferometer (Machzehnder using dual uniform fiber Bragg gratings) is proposed. The tunability of the filter is achieved by wavelength tuning of the fiber Bragg gratings to adjust the basic time delay provided by a dispersive element. Tunability of the filter can be generated by applying mechanical and physical effects which are strain and force on the second arm of homodyne Mach-Zehnder interferometer, i.e., (effected arm). It has been shown from the results that the FBG is very sensitive to variations in strain over a range of (0-0.31) and the normalized sensitivity from 62.8758-62.8743, shifted Bragg wavelength from 1545.726-1545.764 nm, full width at half maximum from 197.529-238.080 pm and power from 12.1-11 nW and in the theoretical optiwave, obtained to the shifted Bragg wavelength from 1454.766-1546.25 nm. It observed that when tensile strain applied to the second arm of homodyne MZI, showed shifting in center wavelength (red shift). Also, observed from the results, the relation between the shifted Bragg wavelength and micro strain is nonlinear.
Aia T. Yhia, Tahreer S. Mansour and Yousif I. Hammadi, 2018. Tunable Notch Fiber Bragg Grating Optical Filter. Journal of Engineering and Applied Sciences, 13: 7450-7458.