Shaping of Picosecond Pump Pulses by SHG Depletion for Wide-Bandwidth TW-Class NOPCPA

Abstract

On a global scale, great efforts were made to create TW-class laser systems [1] based on an Optical Parametric Chirped Pulse Amplifier (OPCPA). The generation of stable white light supercontinuum (WLC) in the wavelength range from ∼ 500 nm to ∼ 1000 nm with picosecond pump pulses [2] simplifies the OPCPA architecture [3] due to the inherent signal and pump synchronization. In the OPA process, the resulting gain depends on the temporal profile of the pump pulse. For strongly chirped signal pulses, the amplification process may possibly lead to a significant decrease in the spectral bandwidth. This problem can be avoided by controlling the temporal shape of the pump pulse. We demonstrate the compact TW-class VIS-IR wavelength range NOPCPA with an almost lossless spectral bandwidth achieved due to the formation of M -shaped ps pumping pulses after the SHG-conversion. Moreover, the reuse of depleted pump pulses after some SHG and NOPA stages provides an increase in the overall pump-to-signal energy conversion efficiency.