Inside a Texas Petawatt shot day: stars in a vacuum chamber, then funding cuts

Two floors beneath the University of Texas at Austin sits the Texas Petawatt, one of the most powerful lasers in the country. From 2020 to 2024, the author led laser science at the facility, which operated as part of LaserNetUS-a Department of Energy network letting researchers nationwide book time on high-power laser systems. The facility is currently shuttered due to funding cuts.

The physics is brute-force elegance: stretch a tiny light pulse so it doesn’t vaporize the optics, amplify it past the instantaneous power output of the entire US electrical grid, then recompress it to roughly a trillionth of a second. The pulse hits targets ranging from sub-hair-width metal foils to gas jets and plastic pellets, briefly creating star-like conditions inside a vacuum chamber.

Research applications spanned stellar interior physics, fusion energy, and cancer therapy approaches. Despite the cinematic framing the technology invites, an actual shot day is hours of methodical preparation around a ten-second window where the experiment either works or doesn’t.