Record Breaking Petawatt Laser Being Built at Lawrence Livermore National Lab

Lawrence Livermore National Laboratory (LLNL; Livermore, CA) has installed and commissioned the highest-peak-power laser-diode arrays in the world, which in total produce a peak power of 3.2 MW. The diode arrays, which were developed and fabricated by Lasertel (Tucson, AZ), will act as the primary pump source for the High-Repetition-Rate Advanced Petawatt Laser System (HAPLS), currently under construction at LLNL. When completed, the HAPLS laser system will be installed at the European Union’s Extreme Light Infrastructure (ELI) Beamlines facility, which is under construction in the Czech Republic. The HAPLS is being built and commissioned at LLNL and will be installed and integrated into the ELI Beamlines facility starting in 2017.

HAPLS is designed to be capable of generating 30 fs pulses with peak powers greater than a petawatt at a repetition rate of 10 Hz. The high repetition rate is possible because, unlike existing petawatt lasers, which are flashlamp-pumped, HAPLS is pumped by diode arrays capable of delivering kilojoule pulses at high repetition rates to the final power amplifier.

Each laser-diode array supplied by Lasertel supplied contains multiple 888 nm laser-diode bars mounted on water-cooled stacks (see figure). The array operates at a brightness of 10 kW/cm2, which Lasertel notes is a world record, at a repetition frequency of 10 Hz. Each array operates at a total peak power of 800 kW, with four such arrays combined and used as the primary pump sources for the HAPLS laser. More than 500,000 combined laser diode emitters combine to produce the total diode optical input power of 3.2 MW.

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