Scientists at the University of Michigan have successfully fired ZEUS (Zettawatt-Equivalent Ultrashort pulse laser System), the most powerful laser ever built in the U.S., generating an astounding 2 petawatts—over 100 times the electricity output of the entire Earth—albeit for just 25 quintillionths of a second.
ZEUS, housed in a gym-sized facility, is the successor to the university’s previous HERCULES laser, which peaked at 300 terawatts. In its first official test, ZEUS fired a laser pulse into a helium-filled target, creating plasma by stripping electrons from helium atoms. These electrons then accelerated behind the laser pulse through a process called wakefield acceleration, gaining incredible speeds inside the target chamber.
Later this year, a more complex experiment will collide these accelerated electrons with laser pulses from the opposite direction, boosting the effective power to a “zettawatt equivalent”—one million times more powerful than the 3-petawatt laser produced in the test.
To protect the equipment and surroundings, ZEUS uses diffraction gratings that stretch the laser pulse, preventing it from damaging the air around it.
Beyond its record-breaking power, ZEUS aims to generate electron beams comparable to those from particle accelerators that are much larger and more costly. Built at just $16 million, ZEUS is considered a budget-friendly breakthrough in laser technology.
ZEUS’s ultra-short bursts of energy are expected to advance research in medical imaging, cancer treatment, and fundamental physics—such as studying positron jets from black holes and gamma-ray bursts.
Franklin Dollar, a University of California physicist involved in the project, highlighted ZEUS as a national resource revitalizing high-intensity laser science in the U.S., offering opportunities for cutting-edge experiments led by the most promising researchers.