55 fs, 510 mW Erbium-Doped Fiber Femtosecond Laser

An erbium-doped fiber laser system based on divided-pulse amplification and fiber nonlinear compression is demonstrated in this paper. The separation and combining of eight replicas arc realized by polarization multiplexing with three length-multiplied YVO4 crystals. The combining efficiency of the main-amplifier with different pulse widths is first investigated. Then, the amplified pulses arc coupled into a single-mode polarization maintaining fiber to be further compressed. The nonlinear compression process is optimized by controlling the pump power of the main-amplifier and the fiber length in the compressor, and the pulses with 55 fs temporal duration, 510 mW output power and 80.4 MHz repetition rate arc generated. Furthermore, the frequency-doubled laser at 783.4 nm with 146 mW average power and 75 fs temporal duration is achieved using a 0.3-mm-length MgO:PPLN crystal, and the corresponding conversion efficiency is 31%.

Automated summary

This paper demonstrates an erbium-doped fiber laser system based on divided-pulse amplification and fiber nonlinear compression. The separation and combining of eight replicas are achieved by polarization multiplexing with length-multiplied crystals, generating pulses with 55 fs temporal duration. Additionally, a frequency-doubled laser at 783.4 nm is achieved with an average power of 146 mW and 75 fs temporal duration using a MgO:PPLN crystal with a conversion efficiency of 31%.