Direct carrier-envelope phase control of an amplified laser system

Here we demonstrate a direct method to stabilize the CEP of an Yb:KGW MOP A laser system, resulting in sub-100 mrad stability. To the best of our knowledge, this value surpasses most previously measured CEP jitter for Ti:sapphire CPA systems as well as any previous attempt to stabilize Yb-based oscillator and amplifier systems. This is a crucial step in widening the utility of amplifier femtosecond Yb sources, which are easily scalable in average power and pulse energy but could not be meaningfully employed in attosecond optics until now, given the difficulty of their CEP control.