Abstract

We present a sub-2 cycle laser system combining high average power, pulse energy and repetition rate with CEP-stable operation making this system an ideal driver for next-generation attosecond sources. The system is based on a fiber-chirped pulse amplification system incorporating coherent combination of 8 amplifier channels. The latter emits 300fs pulses, which are post-compressed down to the few-cycle regime in a two-stage multi-pass cell (MPC) nonlinear pulse compression. The first multi-pass cell is based on standard dielectric mirrors and achieves 1.7mJ, <35 fs pulses. The second MPC utilizes metal-based mirrors allowing to achieve a pulse duration of 5.8fs at a pulse energy of 1.1mJ, which corresponds to the shortest pulses and highest compressed average power for few-cycle MPCs with 110W at the used 100kHz pulse repetition rate. The stabilization of the carrier-to-envelope phase is presented.

© 2021 The Author(s)