Harmonic dissipative soliton resonance in an Yb doped fiber laser with 110 W all fiber polarization-maintaining amplifier

•The harmonic DSR is realized in an Yb-doped fiber laser with large normal dispersion.•Based on an PM MOPA system, the pulses are amplified up to 110 W output power with the PER of 18.7 dB.•A record pulse energy of 0.51 mJ at the frequency of 221 KHz for the pulses is achieved. The formation of harmonic dissipative soliton resonance (DSR) is experimentally investigated in an Yb-doped fiber laser operating in large normal dispersion regime. The DSR is observed at a fundamental frequency of 221 KHz, which delivered square-shaped with of 18.7–98.5 ns and single pulse energy of 0.25 μJ at 1056 nm. By adjusting the PCs, the DSR square pulses could be split into their harmonic mode-locked (HML) counterparts. These experimental results provide a new viewpoint for the further understanding of the mechanism and characteristics of HML square pulses. Based on a two-stage all-fiber PM master oscillator power amplifier (MOPA) system seeded by this oscillator, the pulses are amplified up to 110 W output power with the polarization extinction ratio (PER) of 18.7 dB at different frequencies ranging from 221KHz to 663 KHz and a record pulse energy of 0.51 mJ at the frequency of 221 KHz is achieved.