A picosecond ytterbium-doped double-clad fiber amplifier with a SESAM mode locking PCF oscillator as the seed source

Abstract

We report a picosecond ytterbium-doped double-clad fiber amplifier with a semiconductor saturable absorber mirror (SESAM) mode locking large mode area photonic crystal fiber (PCF) oscillator as the seed source. In the seed source, without any dispersion compensator or tunable elements in the cavity, we obtain self-starting mode locking of a tunable ytterbium-doped fiber oscillator. The 1037-1054 nm tuning range is achieved by proper adjustment of the half-wave plate and SESAM in the laser cavity. More than 1 W output power at the different wavelengths of operation has been achieved in experiments. For the fiber amplifier seeded with an SESAM mode locking PCF fiber oscillator, an average output power of 21 W has been demonstrated at a repetition rate of 45.9 MHz with a pulse duration of 8.8 ps, corresponding to a pulse energy of 458 nJ and a peak power of 52 kW. The nonlinear effect of self-phase-modulation (SPM), which results in spectral broadening, has been observed during the amplified experiments.

120 W subnanosecond ytterbium-doped double clad fiber amplifier and its application in supercontinuum generation

“…As we know, the mode-locking technique is widely used for achieving short pulses in fiber lasers [6,7]. Different types of devices have been exploited for stable passive mode-locking, such as semiconductor saturable absorbers [8], nonlinear polarization rotation (NPR) techniques [9,10], carbon nanotubes [11], atomic layer graphenes [12], etc. Usually, the mode-locking technique is suitable for generating picosecond-and femtosecond-width ultra short pulses.…”