DDF-based all-fiber optical source of femtosecond pulses smoothly tuned in the telecommunication range

The possibility of the creation of an optical source of femtosecond pulses that are smoothly tuned in the telecommunication range using a dispersion-decreasing fiber is demonstrated. The smooth tuning is based on the Raman frequency conversion of ultrashort pulses, which can be effectively tuned due to the compression mechanism for maintaining of a relatively high pulse intensity in the medium with a monotonically decreasing anomalous dispersion. The generation of a 90-fs soliton pulse whose spectrum is smoothly tuned in the wavelength range 1.6-1.8 mu m is experimentally demonstrated.