Generation of TW-scale mid-IR femtosecond pulses using a dual-chirped optical parametric amplification

By using a dual-chirped optical parametric amplification (DC-OPA) scheme, we demonstrate high-energy infrared (IR) pulses with TW-scale peak power in the wavelength region of 1 similar to 3.5 mu m. In the central wavelengths between 1.2 similar to 1.8 mu m, we obtained over 100 mJ pulse energy. DC-OPA, which is an energy scalable method for an OPA process, can allow us to use a joule-class Ti:sapphire laser system for pumping an OPA. To the best of our knowledge, our DC-OPA laser is the first 100-mJ-class IR source with pulse duration of shorter than 100 fs. Additionally, to show the ability of our DC-OPA laser system, we demonstrate an energy-scaling strategy of high-order harmonic driven by a loosely focused 1.5 mu m pulse. Using a 4-cm Ne gas cell with a 3.5-m laser focusing length, soft x-ray harmonics beyond 200 eV are clearly enhanced by a phase-matching effect.