Fig. 1. (Color online) Optimized dispersion profile with D=0+1ps/(nm·km) over a wavelength range of 316 nm and corresponding β2 variation. Top inset: the cross section of the optimized design. Bottom inset: the corresponding 4th-order GVD parameter (β4), which remains positive up until the wavelength value of 1558 nm.

Fig. 2. (Color online) FOPA gain and bandwidth variation as a function of the fiber length for a fixed pump power of 10 W.

Fig. 3. (Color online) FOPA gain and bandwidth variation as a function of the pump power (P) for a 35 m fiber length at λp=1450nm.

Fig. 4. (Color online) (a) FOPA gain and bandwidth variation as a function of pumping wavelength for a pump power of 10 W and a fiber length of 40 m around the ZDW. (b) The phase-mismatch (Δβ) alteration corresponding to (a). The phase-mismatch curve clearly predicts the dip and peak of the FOPA gain spectrum.

Fig. 5. Optimized parametric gain spectrum for a bandwidth of 223 nm. Inset: the corresponding Δβ variation. The net gain took place for −4γP≤Δβ≤0 while the maximum gain corresponds to Δβ=−2γP.