Extreme picosecond pulse narrowing by means of soliton effect in single-mode optical fibers

We report the narrowing of pulses, initially 7 psec FWHM, to widths as small as 0.26 psec by various lengths, short relative to the soliton period, of single-mode, low-loss optical fiber. Since the ~1.5-microm wavelength lies in the region of negative group-velocity dispersion ( partial differentialv(g)/ partial differentiallambda < 0), no auxiliary dispersive element was required to complete the narrowing. Optimum compression was obtained for peak-pulse input powers of several hundred watts, corresponding to relatively high (N > 10) soliton number. We show these results to be in at least semiquantitative agreement with prediction based on the nonlinear Schrödinger equation.