Abstract

Three-wave interaction of ultrashort light pulses is always affected by group-velocity-mismatch (GVM) which tends to separate the interacting pulses, and group-velocity-dispersion (GVD), responsible for pulse broadening. There are two relevant regimes of pulse compression via three-wave interaction in χ⁽²⁾ materials: (i) if the GVM dominates and the low-frequency pulses run with opposite velocities respect to the high-frequency one, then interaction could lead to the so called "non-linear pulse compression" (NPC), (ii) if the GVD dominates and has the same sign for all three waves, then mutually-trapped dispersion-free bright temporal solitons [soliton pulse compression (SPC)] are attained. Unfortunately, with conventional plane pulses, the NPC is not easy to achieve, since very specific wavelengths and crystals are required¹; even more critical are requirements for the SPC, since the GVM actually dominates over the GVD in all experimentally accessible conditions.

© 1999 Optical Society of America