Direct demonstration of distortionless picosecond-pulse propagation in kilometer-length optical fibers

We describe the use of a mode-locked color-center laser to demonstrate nearly distortionless propagation of ~5-psec-wide, Fourier-transform-limited pulses, at or near the zero-dispersion wavelength, in two fused-silica, singlemode fibers of 0.76- and 2.5-km length, respectively. We also report the detection of sharply defined cross correlations between pulses directly from the laser and those had been delayed many microseconds by passage through a fiber.