Sub-Hz drift dominates full-band phase noise of the feed-forward system. This review models its mechanisms through phase-noise integration and transfer functions.
We critically review carrier-envelope phase stabilization of Er:Yb:glass mode-locked lasers, reproducing attosecond-level jitter and illustrating that millisecond-level upper-state lifetime limits bandwidth, forcing a hybrid feed-forward/feedback architecture and motivating fast intracavity actuation.
