Spectra of dual-overwritten chirped fiber Bragg gratings

Abstract

The coupled-mode equations for dual-overwritten chirped fiber Bragg gratings (CFBGs) are obtained and numerically calculated. By simulating the reflection spectra of dual-overwritten CFBGs, we have investigated the effects of chirp coefficient, period difference, grating length and index modulating coefficient, on the reflection spectrum and its intensity and full-width-at-half-maximum (FWHM).

Keywords:

• fiber Bragg grating
• dual-overwritten chirped FBG
• coupled-mode theory