Long-term CEP-stable few-cycle pulses using the feed-forward method in an all-monolithic setup

The rapid progress in many areas of ultrafast science is steadily increasing the requirements on carrier-envelope phase (CEP) stabilization. While suitable sources for attosecond/high-field experiments remain limited to kHz repetition rates, two factors are of key importance to successful experiments: Tight CEP control and robustness over long timescales. Utilizing a phase-locked loop, the conventional CEP locking scheme inevitably implies a trade-off between these two. On the other hand, applications for few-cycle pulses directly from the oscillator greatly benefit from f_ce = 0, which comes at an expense of performance and increased complexity.