Alternating fiber segments minimize four-wave mixing and dispersion
Researchers at Corning Inc. (Corning, NY) have come u¥with a simple system to minimize nonlinear effects such as four-wave mixing (FWM) and dispersion that occur in optical systems with more than 32 channels covering distances of more than 500 km without repeaters. The method is based on a continuous fiber with alternating sections of positive and negative dispersion built in. Continuous lengths of fiber were fabricated without any splicing by an outside vapor-deposition process. The researchers obtained fiber-attenuation values as low as 0.21 dB/km, similar to those of uniform fibers.
"A very important characteristic of these novel fibers is their significantly reduced FWM efficiency," notes Venkata Baghavatula, who will present the results on Feb. 24 at the annual Optical Fiber Communication conference (San Jose, CA; see related story on p. 20). "Modeling results indicate that such axially varying dispersion-managed fibers can be designed to have FWM efficiency lower than present finite-dispersion fibers while maintaining zero or low dispersion in the erbium amplifier window," he said.