Efficient generation of all-fiber femtosecond pulses at 1.7 μ m via soliton self-frequency shift

Soliton self-frequency shift (SSFS) is a nonlinear effect that generates wavelength-shifted laser pulses in optical fibers. Based on SSFS, we report the generation of ultrashort pulses emitting at 1.7-μm band in a common dispersion shifted fiber (DSF) pumped by an ultrafast Er-doped fiber laser. Through optimizing the DSF length, sub-200 fs pulses in the range from 1.70 to 1.74 μm have been achieved with >76% conversion efficiency. The maximum output power is 26.8 mW and the single pulse energy is up to 0.7 nJ. Numerically, simulations have been carried out to map the SSFS pulse evolution in DSF. The simulation results are in a good agreement with the experiment results, giving the feasibility of this method.