RESUMO
Two-stage multipass-cell compression of a fiber-chirped-pulse amplifier system to the few-cycle regime is presented. The output delivers a sub-2-cycle (5.8â fs), 107â W average power, 1.07â mJ pulses at 100â kHz centered at 1030â nm with excellent spatial beam quality (M2 = 1.1, Strehl ratio S = 0.98), pointing stability (2.3â µrad), and superior long-term average power stability of 0.1% STD over more than 8â hours. This is combined with a carrier-envelope phase stability of 360â mrad in the frequency range from 10â Hz to 50â kHz, i.e., measured on a single-shot basis. This unique system will serve as an HR1 laser for the Extreme Light Infrastructure Attosecond Light Pulse Source research facility to enable high repetition rate isolated attosecond pulse generation.