Polariton-induced compensation of pulse broadening in optical fibers

We report the first experimental technique for compensating the pulse broadening in single-mode optical fibers, using the ’’slow’’ anomalous pulse propagation in the exciton-polariton resonance in a direct-gap semiconductor. Mode-locked dye laser pulses of 0.7-ps duration at 8180 Å were propagated through a 100-m single-mode optical fiber and emerged with 2.8-ps duration. We have demonstrated the compensation of this pulse broadening in optical fibers by passage through a 6.3-μm-thick GaAs crystal, taking advantage of the group velocity dispersion around the discrete n = 1 exciton-polariton resonance.