SUBFEMTOSECOND PULSES IN THE MULTICASCADE STIMULATED RAMAN-SCATTERING

We explore recently predicted multifrequency 2 pi solitons in multicas cade stimulated Raman scattering (SRS) that was mode locked by the dyn amics of population at a Raman quantum transition; we show that these solitons are eigensolitons of a general solitary-wave solution. Solito n components at each frequency are bright pulses of the same (Lorentzi an) shape, in contrast to the familiar bright-dark soliton pair in reg ular SRS and to 1/cosh regular 2 pi solitons. Coherent interference of these components gives rise to a train of well-resolved subfemtosecon d pulses. From an observation viewpoint the simplest SRS 2 pi solitons are so-called bright-bright solitons in noncascade SRS with either tw o (laser + Stokes) or three (e.g., laser + Stokes + anti-Stokes) compo nents. (C) 1996 Optical Society of America