In this letter we report a simple single-stage amplifier realized as high as 62 W average power output at 1064 nm wavelength, 40 picoseconds pulse width and 80 MHz repetition from 0.7 W seed laser based on backward pumped masteroscillator fiber power amplifier (MOPA) system. It is can stable operation in 57.6 W output for hours. We applied a semiconductor saturable absorber mirror (SESAM) passive mode-lock Nd:YVO4 oscillator as seed source and 6m long 20 µm core double-cladding Yb-doped fiber (YDF) as gain medium. To the best of our knowledge, 62 W average power is the highest output of single-stage ps-pulse amplifier with 20 µm-core fiber. None amplified spontaneous emission (ASE) and stimulated Raman scattering (SRS) nonlinear phenomenon was observed in 57.6 W high average power output.

In this paper, we report 38.8 W average power output through a single-stage fiber amplifier, with emission of 1064 nm wavelength with 80 MHz repetition and 35 ps pulse width amplified from a 2.15 W SESAM passively mode-locked Nd:YVO 4 laser oscillator. The high power fiber amplification is through a coupled 60.8 W 976 nm backward unidirectional pump power into a 2 m long 30/250 µm Yb-doped inner cladding. No obvious nonlinear effects arise in the high power output. To our knowledge this is the highest average power output with 2 m 30/250 µm Yb-doped double-clad fiber in a single-stage picosecond fiber amplifier.