102 kHz repetition rate dissipative soliton mode-locked Yb-doped fiber using Nb₂CTx/ZnO composite as saturable absorber

A 102 kHz repetition rate of dissipative soliton mode-locked pulses was experimentally achieved in this work. The oscillator was based on normal dispersion, with the Nb2CTx/ZnO composite acting as the saturable absorber, which was fabricated using the delamination and hydrothermal methods. This output was a dissipative soliton at a fundamental repetition rate of 40.6 MHz and a pulse width of 8.4 ps. By amplifying the seed pulses through a ytterbium-doped fiber amplifier, an average optical output power of 104 mW was achieved. These amplified mode-locked pulses were then passed through an acousto-optic modulator with a pulse picker module to lower the repetition rate. After the pulse-picking process, a repetition rate of 102 kHz was achieved with a pulse duration of 11.4 ps. At the same time, it increases the pulse energy of the mode-locked pulses from 0.1 nJ (at the oscillator) to 22.5 nJ (after the pulse picker) and the peak power from 4.8 W to 1.9 kW. This experimental configuration demonstrates the scalability of pulse energy without compromising the dispersion and cavity length of the oscillator, resulting in no significant broadening of the pulse duration.