Modelling of Praseodymium-Doped Fluoride and Sulfide Fibre Amplifiers for the 1.3um Wavelength Region

摘要

In optical communication systems, the use of optical amplifiers opens the way toan increased system performance, particularly in loss-limited long-haul systems, in dispersion limited systems and also in subscriber access systems to compensate for splitting losses. For the 1.3 micrometer wavelength region, the Praseodymuim-doped fiber amplifier (PDFA) is a promising candidate. A numerical model is used to compare the characteristics of Pr(+3)-doped fibers on the basis of bulk glass properties. It incorporates the distribution of the optical modes across the fibers cross-section in order to find the optimum cut-off wavelength and numerical aperture of the fiber. The model includes excited-state absorption, signal ground-state absorption, and background losses. Furthermore, all forward and backward traveling noise is included. PDFA's based on sulfide glasses have a considerably improved efficiency compared to amplifiers based on ZBLAN fluoride glasses.