The HAPPIE Joint Research Activity built on high power/high rep rate European project investments. It targeted new technological developments centred on a high power mission, and was aligned to a vision of future high average, high peak power developments with:
MBI (left) and LULI (right) DPSSL laser heads
The activities of objective 1 (DPSSL) were dedicated to face pumped
thin disc technology and photonic rod fibres. Within
- MBI developed a multipass amplifier with 17 mm disc diameter delivering more than 550 mJ at a 100 Hz repetition rate.
- FSU concentrated its efforts on cryogenic studies with an efficient (>45%) CaF2 laser source delivering more than600 mJ.
- IST developed a Yb-based diode-pumped amplifier delivering 80 mJ at 0.5 Hz.
- LULI was able to achieve more than 10 joules at 2Hz with a water jets cooled Yb:YAG disk amplifier.
- CELIA developed a 47 fs photonic rod laser system delivering 8.6 W
Activities for objective 2 (parametric conversion) were dedicated to non-linear combination, ultra-high contrast and OPCPA optically synchronized schemes:
- STFC developed a Joule level/35 fs laser system with a contrast after compression measured at 106 at 10ps and 1011 at 5ns.
- GSI reduced ASE with pulses partly stretched early in itsamplifier chain.
- CEA measured thermal lensing in Ytterbium doped sesquioxides thin-disks lasers at low temperature and estimated the associated radiative quantum efficiency
- CNR added an OPCPA preamplifier stage to its BLISS laser system while
- VULCR developed a high contrast NIR OPCPA system with an enhanced signal/ASE energy contrast.
- Finally, USZ developed a 150 fs 200 μJ source whereas
- PIVUT developed a mid-IR 3.9 μm OPCPA delivering 12-mJ 80 fs pulses at 20 Hz.
Activities for objective 3 (coherent aperture combination) were essentially dedicated to non-linear conversion schemes:
STFC laser testbed for contrast studies