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Fiber Bragg grating for optical dark soliton generation

We investigate theoretically and experimentally the generation of dark soliton pulse trains at several gigahertz repetition rate by means of a fiber Bragg grating used as a passive filtering element at the output of a mode-locked laser. We show that a proper choice of the grating parameters allows for the transformation of bright pulse train into odd dark pulse trains with continuous-wave (CW) background.