Two-pump fiber optical parametric amplifiers using optimized photonic crystal fiber by genetic algorithm

In this paper, we investigate the gain spectra of fiber optical parametric amplifiers (FOPAs) consisting of dispersion-flattened fibers (DFFs) with different dispersion curves comparatively by means of the dispersion curve model of the DFFs. It is demonstrated that the broader gain spectrum of FOPAs can be achieved if the dispersion curve is lower and more flattened. Based on the preceding analyses, we propose to constitute FOPAs by using index-guiding photonic crystal fiber (PCF) with an anticipated ultra-flattened dispersion and ultra-low dispersion slope. The as-proposed PCF had different air-holes in the cladding rings. In total, four parameters of the PCF are optimized by using genetic algorithm. PACS 42.81.-i; 42.65.Hw; 42.65.Yj