Millijoule Ultrafast Optical Parametric Amplification as Replacement for High-Gain Regenerative Amplifiers

We report on the development of an ultrafast optical parametric amplifier (uOPA) front-end for the Petawatt High Energy Laser for heavy Ion eXperiments (PHELIX) and the Petawatt ENergy-Efficient Laser for Optical Plasma Experiments (PE NELOPE). This front-end delivers broadband and stable amplification up to 1 mJ per pulse while maintaining a high beam quality. Its implementation at PHELIX allowed to bypass a front-end amplifier that was known to be a source of pre-pulses. With the bypass, an amplified spontaneous emission (ASE) contrast of 4.9·10−13 and a pre-pulse c ntrast
of 6.2·10−11 could be realized. Due to its high stability, high beam quality and its versatile pump amplifier, the system
offers an alternative for high-gain regenerative amplifiers in the front-end of vario