Pulse Broadening in Multimode Optical Fibers with Large Delta n/n. Numerical Results

The rms impulse response width of germania doped fibers having power-law profiles at the carrier wavelength is evaluated with the help of a numerical method. For Delta n/n x 0.02, the numerical result exceeds by more than one order of magnitude that obtained from an analytical formula based on the assumption that dn ² / d lambda varies linearly with n ². Our numerical technique is based on scalar ray optics. It is applicable to any fiber having a large V-number and a smooth profile.