Propagation of ultrashort dichromatic solitons in a cascade three-level system

摘要

Propagation of dichromatic femtosecond laser pulses tuned respectively in single-photon resonances with the cascade three-level system is studied. The initial areas of the two pulses are both equal to 2π, which makes them respectively an optical soliton in ideal two-level systems. When the dichromatic solitons are synchronized into the medium, both the temporal shapes and the spectral distributions of the pulses are strongly distorted during propagation. The delay time between the dichromatic solitons plays an important role on the evolution of the fields.