The largest vacuum compressor in the Czech Republic belongs to ELI Beamlines

On November 1st, 2017, the vacuum compressor of PW laser pulses for the laser system L3 (one of the four lasers at ELI Beamlines) arrived in Dolní Břežany from Brno. It is the largest vacuum opto-mechanical unit ever designed and manufactured in the Czech Republic.

The company, Delong Instruments, which is focused on the development of advanced technologies and R&D, has been working together with scientists from the Physics Institute of the ASCR on the development of this optical compressor. The conceptual design of the compressor was developed by the Physics Institute in 2014-2015 and the final design, the production and testing itself at Delong Instruments took place between January 2016 and summer 2017.

In the optical compressor, which weighs more than ten tons and measures two and half meters in height and five meters in length, the output laser pulses will be compressed to a length of 30 femtoseconds. This is the time at which the light travels 9 micrometers, about a tenth thickness of human hair. To do this, the laser pulses are shortened by more than 10,000 times using the diffraction gratings placed in the ultra-pure vacuum compressor environment - that is equivalent to shortening the timescale from approximately 3 hours to 1 second.

"Compressor requirements are unusually strict. All of its systems must provide extremely high stability, better than a thousandth of a millimeter, for the smooth operation of the pulse compression process," explains Bedrich Rus, the head of laser technologies at ELI Beamlines. "It is the most dimensional vacuum, opto-mechanical and electronic unit we have so far done for research and development," adds Martin Hlaváč, the project manager at Delong Instruments.

The L3 laser system, including the vacuum compressor, will be the proud holder of many records - not only it will become the world's largest petawatt laser system, but it will also have the world's most powerful pulsed laser diodes and the largest optometric vacuum structure ever designed and manufactured in the Czech Republic.