2-μm wavelength, high-energy Ho:YLF chirped-pulse amplifier for mid-infrared OPCPA

A 2-μm wavelength laser delivering up to 39-mJ energy, ∼10  ps duration pulses at 100-Hz repetition rate is reported. The system relies on chirped pulse amplification (CPA): a modelocked Er:Tm:Ho fiber-seeder is followed by a Ho:YLF-based regenerative amplifier and a cryogenically cooled Ho:YLF single pass amplifier. Stretching and compressing are performed with large aperture chirped volume Bragg gratings (CVBG). At a peak power of 3.3 GW, the stability was <1%  rms over 1 h, confirming high suitability for OPCPA and extreme nonlinear optics applications.