WHAT JUST HAPPENED? The world's largest privately owned laser has switched on in Denver, though it's not part of a Bond villain's plan to carve their name into the moon, sadly. Fusion startup Xcimer Energy has begun operations at Phoenix, a prototype system designed to test whether laser-driven fusion could one day produce commercial electricity.
Housed inside Xcimer's 74,000-square-foot laser facility, Phoenix uses a krypton fluoride excimer laser, a gas-laser design related to technology used in semiconductor manufacturing, albeit at a much larger scale.
The system's light source operates at pulse energies of more than 1 kilojoule, while its core optical system includes a 38-meter-long gas optic used for stimulated Brillouin scattering pulse compression.
Xcimer's approach involves taking a relatively long, microsecond-scale laser pulse and compressing it into the nanosecond timescales needed for inertial fusion. The goal is to deliver an enormous amount of energy to a tiny fuel target quickly enough to force atoms to fuse, releasing energy in the process.
The company's fusion work is modeled after the National Ignition Facility, which in 2022 became the first lab to demonstrate scientific breakeven in a controlled fusion experiment. NIF uses 192 laser beams to blast a tiny fuel target, and in 2025 produced 8.6 megajoules of fusion energy from about 2 megajoules of laser energy delivered to the target.
