Highest peak power from a normal-dispersion Yb-fiber oscillator with anomalous dispersion higher-order-mode fiber

In this contribution we present a passively ML Yb-fiber oscillator that uses a higher-order mode (HOM) fiber [1] for dispersion compensation and operates in the net normal dispersion regime. The HOM fiber allows reducing the repetition rate of the system without compromising pulse duration and pulse quality. Pulse energies of up to 6 nJ were achieved and pulses as short as 150 fs were generated.