Development of a high-average-power microsecond erbium–ytterbium-doped fiber laser system

We report a 200 kHz master oscillator power amplifier erbium–ytterbium-doped fiber laser system at a wavelength of 1548.7 nm with a constant pulse energy of ∼190 μJ providing a tuneable pulse duration of 2 to 5μs. The all-fiber laser system consists of a gain-modulated laser diode used as a seeder, two pre-amplifiers, and a booster amplifier. The output power of the laser system after collimation was 38.24 W, with a root mean square instability of 0.19% providing an excellent performance under environmental perturbations. The beam quality factor was estimated to be M2(x) = 1.08 in the horizontal and M2(y) = 1.09 in the vertical planes indicating a near-diffraction-limited laser beam. After synchronization to femtosecond pulses, the obtained μs laser pulses are expected to contribute to novel microprocessing of semiconductors. •A high-average-power master oscillator power amplifier erbium–ytterbium-doped fiber laser system is developed.•Technical details on the laser development and thermal management are reported.•A constant pulse energy of ∼190 μJ with a tuneable pulse duration in a range of 2 to 5μs is achieved.•Potential application in ultrafast and crack-free micro-processing is discussed.