Laser science at the 100-terawatt (10^14 W) peak-power level has entered the commercial realm. An ultrafast Ti:sapphire laser system produced by Thales Laser (Orsay, France) and installed at the University of Nebraska, Lincoln (UNL; Lincoln, NE) reaches a 150 TW level and is upgradeable in the future to above the petawatt mark. Called Diocles, the laser, considered a fully commercial product, is enabling Donald Umdstadter’s group at UNL’s new Extreme Light Laboratory to perform day-to-day, stable, reproducible ultrafast experiments with an uptime much higher than that of pre-existing lasers of the same power scale. As such, it may usher in a new era of R&D with ultrapowerful lasers.The Ti:sapphire oscillator is pumped with a continuous-wave green laser, the first amplifier is pumped with a 1 kHz diode-pumped Nd:YLF (yttrium lithium fluoride) frequency-doubled laser, and the three medium-to-high-power stages are pumped with 10 Hz frequency-doubled lamp-pumped Nd:YAG lasers. “The hybrid diode/lamp architecture is there to provide high beam quality and stability on the initial low-energy stages (diode pumped), and low-cost energy input for the high-energy stages (flashlamp pumped),” says Marquis. The pump lasers are all water-cooled via a water-water exchanger; the Ti:sapphire laser crystals are also water-cooled via a patent-pending technique that avoids the need for cryogenic cooling. The uncompressed output of the final amplifier exceeds 5 J at a 10 Hz pulse-repetition rate. The laser’s final output beam exceeds a Strehl ratio of 0.7.
Source: Laser Focus World
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