High-Contrast Opcpa Front End In High-Power Petawatt Laser Facility Based On The Ps-Opcpa Seed System

A high-energy, high-beam-quality, high-contrast picosecond optical parametric chirped-pulse amplification (ps-OPCPA) laser system was demonstrated. The pulse from a femtosecond oscillator was stretched to 4 ps, after which it was amplified from 140 pJ to 600 mu J by an 8 ps/6 mJ pump laser in two non-collinear OPCPA stages. The total gain was >10(6), and the root mean square of the energy stability of the laser system was 1.6% in 10 h. The contrasts of the solid and fiber mode-locked femtosecond oscillator-seeded ps-OPCPA systems were compared, and a signal-to-noise ratio of >10(11) was achieved. Using this system, the contrast of the front end in high-power picosecond petawatt laser facility was improved by similar to 40 dB to >10(11), beyond similar to 200 ps ahead of the main pulse with an output level of 60 mJ. (C) 2021 Optical Society of America under the terms of the OSA Open Access Publishing Agreement