COMET user
Postdoctoral researcher, LLNL
Elizabeth Grace, a postdoctoral researcher and High Energy Density Science fellow at LLNL, first used the COMET short-pulse laser in 2018 while completing her PhD thesis on ultrashort laser pulse diagnostics, and it has been a large part of her ongoing postdoctoral work in pump‒probe experiments. “My work can be used to better understand laser pulses and their interactions with matter,” said Grace. Most high-intensity laser applications today do not involve on-shot characterization of the laser pulse due to the complexity of its four-dimensional electric field. However, accurate and precise characterization of the laser field is necessary to predict the impact of the laser and subsequent dynamics, e.g., the impact of the accelerated ion beams, which may be used for cancer therapy and fast ignition for inertial fusion energy.
With COMET, Grace also works on single-shot, time-resolved optical probe diagnostics that can produce a movie of the plasma dynamics for every laser shot, helping to quantify the shot-to-shot fluctuations in laser-plasma dynamics. Typically, this would require a series of identical laser pulses and identical targets to form a sequence, which can be difficult to produce due to the unstable nature of high-energy systems. Grace said, “Single-shot diagnostics, like the one I am developing, can provide a more complete picture of each interaction, giving unprecedented insight into how various ‘small-scale’ changes can drastically affect outcomes.”
