Pulse delay measurements in the zero material dispersion wavelength region for optical fibers

Subnanosecond pulses in the 1120-1550-nm region are generated by multiple-order stimulated Raman scattering in a small core single-mode silica fiber pumped by a Q-switched and mode-locked Nd:YAG laser at 1064 nm. These near ir pulses are injected into various km long test fibers, and relative time delay changes between different wavelengths are used to determine dispersion in a region where fiber material dispersion is small. Zero material dispersion has been observed in germanium and boron-doped single-mode and multimode est fibers.