Title :
Fiber Bragg grating spectra in multimode optical fibers
Author :
Lu, Changgui ; Cui, Yiping
Author_Institution :
Dept. of Electr. Eng., Southeast Univ., Nanjing, China
Abstract :
Bragg gratings in optical fibers in multimode propagation are investigated theoretically by using the coupled-mode theory and considering two modes coupling. Bragg gratings in multimode fibers (MMFBGs) show multiple reflection peaks due to the coupling between all bounded modes. The reflection spectra depend on the excitation condition of the bounded modes. A numerical method based on the fourth-order Runge-Kutta formula is developed to solve the coupled equations. The reflection spectra of Bragg gratings with sinusoidal and square refractive index modulations were simulated. The asymmetric change of refractive index in the cross section is also considered here. The spectra characteristics and potential applications of these gratings are discussed.
Keywords :
Bragg gratings; Runge-Kutta methods; coupled mode analysis; optical fibre theory; reflectivity; refractive index; bounded modes; coupled-mode theory; fiber Bragg grating spectra; fourth-order Runge-Kutta formula; multimode optical fibers; reflection spectra; refractive index modulation; Bragg gratings; Diffraction gratings; Fiber gratings; Optical coupling; Optical fiber communication; Optical fiber devices; Optical fiber sensors; Optical fiber theory; Optical fibers; Optical reflection; Coupled-mode theory; Runge–Kutta formula; fiber Bragg grating; multimode fiber (MMF);
Journal_Title :
Lightwave Technology, Journal of
DOI :
10.1109/JLT.2005.859841
