Using a zero-offset carrier-envelope locking technique, we have synthesized an octave-spanning composite frequency comb exhibiting 132-attosecond timing jitter between the constituent pulses over a one-second observation window. In the frequency domain, this composite comb has a modal structure and coherence which are indistinguishable from those of a comb that might be produced by a hypothetical single mode locked oscillator of equivalent bandwidth. The associated phase stability enables the participating multi-color pulse sequences to be coherently combined, representing an example of multi-pulse synthesis using a femtosecond oscillator.
Mccracken, R.A., Gianani, I., Wyatt, A.S., & Reid, D.T. (2015). Multi-color carrier-envelope-phase stabilization for high-repetition-rate multi-pulse coherent synthesis. OPTICS LETTERS, 40(7), 1208-1211 [10.1364/OL.40.001208].