Dispersion-shifted fiber (DSF), specified in ITU-T G.653, is a type of single-mode optical fiber with a core-clad index profile tailored to shift the
zero-dispersion wavelength from the natural 1300 nm in silica-glass fibers to the minimum-loss window at 1550 nm. The
group-velocity or intramodal dispersion which dominates in single-mode fibers is comprised of both material and waveguide
dispersion. Waveguide dispersion can be made more negative by changing the index profile and thus be used to offset the fixed
material dispersion, shifting or flattening the overall intramodal dispersion. This is advantageous because it allows a
communication system to possess both low dispersion and low attenuation. However, when used in wavelength division multiplexing systems, dispersion-shifted fibers can suffer from
four-wave mixing which causes intermodulation
of the independent signals. As a result nonzero dispersion shifted
fiber is often used.
References
- L.G. Cohen, C. Lin, and W. G. French, Electron. Lett., 15, 334 (1979).
This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)