085 PW laser operation at 33 Hz and high-contrast ultrahigh-intensity λ = 400 nm second-harmonic beamline

Abstract

We demonstrate the generation of 0.85 PW, 30 fs laser pulses at a repetition rate of 3.3 Hz with a record average power of 85 W from a Ti:sapphire laser. The system is pumped by high-energy Nd:glass slab amplifiers frequency doubled in LiB₃O₅ (LBO). Ultrahigh-contrast λ=400 nm femtosecond pulses were generated in KH₂PO₄ (KDP) with >40% efficiency. An intensity of 6.5×10²¹ W/cm² was obtained by frequency doubling 80% of the available Ti:sapphire energy and focusing the doubled light with an f/2 parabola. This laser will enable highly relativistic plasma experiments to be conducted at high repetition rate.