I’ve fired one of America’s most powerful lasers—here’s what a shot day looks like

Beneath the University of Texas at Austin campus lies the Texas Petawatt (TPW), one of the most powerful lasers in the United States, capable of producing a pulse with more power than the entire US electrical grid for a trillionth of a second. From 2020 to 2024, the TPW operated as a government-funded research facility within the Department of Energy’s LaserNetUS network, allowing scientists nationwide to conduct experiments ranging from stellar physics and fusion energy to innovative cancer treatments. The laser’s operation involved stretching, amplifying, and compressing light pulses to create extreme conditions, such as generating a star-like plasma in a vacuum chamber. A typical “shot day” at TPW was a meticulous process requiring hours of preparation and precision. The lead laser scientist would begin early, donning cleanroom attire before initiating the laser’s oscillator and pump laser systems. These components generate and amplify the initial light pulse, which must remain stable and perfectly aligned throughout the setup. The actual laser shot, lasting only about 10 seconds, was the culmination of extensive calibration and quiet focus, with the team ensuring every parameter—from energy levels to vacuum pressure—was exact to guarantee consistent performance for scientific experiments. The TPW’s closure due to funding cuts marks a significant setback for high-power laser research in the US, as the facility was a critical tool for advancing knowledge in multiple scientific fields. Its unique capabilities enabled researchers to simulate extreme environments and explore fundamental physics questions that are otherwise impossible to recreate. The shutdown highlights ongoing challenges in sustaining large-scale scientific infrastructure, which impacts the broader research community’s ability to innovate and collaborate on cutting-edge projects. Currently, the former lead scientist continues research at the University of Texas, focusing on laser-material interactions, underscoring the ongoing importance of high-power laser technology despite the TPW’s hiatus. The story of TPW illustrates both the complexity and potential of laser science, as well as the delicate balance between scientific ambition and funding realities.