Performances of straight and bent dispersion decreasing fiber amplifiers in parabolic similariton pulse formation

This work reports the performances of straight and bent normal dispersion decreasing fiber amplifiers (NDDF) to generate self-similar parabolic pulses, including the spatial variation of nonlinear factor. The dispersion tapering along the fiber length of the proposed NDDF is obtained in presence of the external gain. For varying core radii along the fiber length, bend loss being no longer a constant quantity, loss variation along the transmission length must be considered. The comparative study on the optimum fiber length of NDDF with a range of bend radii of curvatures for bent as well as for straight NDDF is useful for fiber optic designers or manufacturers. The study shows that such active NDDFs are capable enough to generate self-similar parabolic pulses even when the bending is considered, though optimum length is increased to some extent.