An all-fiber high-power picosecond amplifier with Yb-doped polarization-maintaining tapered fiber

Abstract A high-power picosecond all-fiber master oscillator power amplifier (MOPA) was demonstrated based on the Yb-doped polarization-maintaining (PM) tapered double-clad fiber (T-DCF). An all-fiberized pumping unit instead of the free space pumping structure was adopted in the MOPA system to provide a compact robust solution for high-performance amplifiers. The total average output power of 180.3 W was achieved with a slope efficiency of 80.8% by taking advantages of the large fiber mode area and the suppression of nonlinear effects in the T-DCF. The peak power was calculated to be 27.7 kW at the pulse width of 260.8 ps and the repetition rate of 24.91 MHz. The polarization extinction ratio and beam quality ( M 2 factor) were measured to be ∼10 dB (91%) and ∼ 12, respectively.