Reverse dispersion fiber with depressed core-index profile for dispersion-managed fiber pairs

A reverse dispersion fiber (RDF) with depressed core-index profile has been developed successfully by using plasma chemical vapor deposition (PCVD) process. The fabricated RDF has a core-effective-area of 45 μm2, a dispersion of −19.65 ps/nm/km and a dispersion slope of −0.132 ps/nm2/km while maintaining the low bending induced attenuation and low PMD value. The dispersion-managed pairs, which consisted of RDF and non-zero dispersion shifted fiber with ultra large effective core-area (ULAF), have the ultra low dispersion slope of less than 0.006 ps/nm2/km at the wavelength range of 1530-1625 nm, and the largest dispersion value is lower than 0.2 ps/nm/km. Moreover, the attenuation characteristic also shows a remarkable flatness over the broadband wavelength, the attenuation at 1550 nm is only 0.224 dB/km. The dispersion-managed pairs are suitable for large capacity, high bit-rate long-haul wavelength division multiplexing (WDM) transmission system without using dispersion compensation mode.