Flexible YB-doped fiber laser generating a single-transverse mode beam with UP to 0.5mJ/11W

We demonstrate a flexible Yb-doped fiber laser that can generate up to 0.5mJ output energy or 11W average output power. The 1064nm single mode beam of a diode laser is amplified by a three stage amplifier. The first two amplification stages consist of single-mode fibers. The third stage uses LMA fiber. The output beam of the first two amplification stages is coupled into the LMA fiber of the third stage via an adiabatic taper in a monolithic setup. Various pulse parameters were investigated in the range from 10kHz to 1MHz. The system achieves an output energy of up to 0.5mJ and a maximum peak power of 65kW. Also, pulse trains were investigated. The system generated four 10ns pulses with pulse spacing of 200, 500 and 1000ns. The pulse trains were repeated at 1kHz.