Short-pulse optical parametric chirped-pulse amplification for the generation of high-power few-cycle pulses

This paper demonstrates ultrabroadband optical parametric chirped-pulse amplification (OPCPA) with 100-fs pulses in the 100-muJ range. By using OPA for amplifying mainly the weak part of the filament-broadened spectrum much shorter pulses with an improved uniformity of the spectral intensity can be achieved as compared to the direct compression of the filament output. In order to increase the signal pulse energy to the multi-mJ level an improved spatial filter using a tapered glass capillary pinhole is under construction to allow for using a much larger part of the ATLAS output energy for pumping. Furthermore, the high available seed energy of 1 mJ could allow for reaching the 100 mJ level with small amplification factors in a multi-stage OPCPA system where saturation in all stages is beneficial for signal stability and pulse contrast. Scaling of the short-pulse OPCPA scheme to petawatt level is also planned.