Wavelength tunable repetition rate doubled pulse generation through a nonlinear optical loop mirror

In this paper we demonstrate tunable wavelength (1537-1562 nm) ultrastable optical pulse train generation at 38 GHz by a NOLM made of dispersion shifted fibre (DSF) in conjunction with a hybrid mode-locked laser operating with a repetition rate of 38 GHz used as the input pulse source. The use of hybrid mode-locked laser provides the added advantage of synchronizing the generated pulse trains to an external electrical signal. Also, we observe for the first time, to the best of our knowledge, repetition rate doubling in NOLM resulting in generation of 76 GHz pulse trains. This is achieved by the suppression of the optical carrier wavelength of the wavelength converted signal utilizing NOLM dynamics. Optimizing this effect may facilitate the increase in repetition rate according to network demand in future demand oriented WDM networks