Laser uranium enrichment has been proven to work in labs for over 50 years, but no one has been able to commercialize it. The technology works, but scaling it has proven insurmountable.
A startup based in Oak Ridge, Tennessee, is tackling the scaling problem. LIS Technologies was founded by a team with roots in ASML, the Dutch lithography giant whose laser-driven systems are central to advanced chip manufacturing.
LIS Technologies is betting on CRISLA (Condensation Repression Isotope Selective Laser Activation), a different way to enrich uranium. The method was invented by Jeffery Eerkens in the 1970s, but it was shelved when the Cold War ended, and Russian enriched uranium was dumped on the world markets.
How the Cold War created dependence on Russia
During the Cold War, Russia enriched massive amounts of uranium for its nuclear weapons. When the Cold War ended, the U.S. and Russia made a deal to decommission their nuclear weapons and reduce the uranium from 90% to 5%. The U.S. imported this uranium from Russia to power nuclear reactors.
“We’ve become dependent on Russian nuclear fuel,” Christo Liebenberg, co-founder and president of LIS Technologies, explained, “and this decimated the entire nuclear fuel supply chain.”
In 2024, the U.S. enacted a ban on low-enriched uranium (LEU) imported from Russia until 2040 (although waivers are permitted through Jan. 1, 2028), putting further pressure on the issue. “We produce only 4.5 million SWU per year on U.S. soil. We have to go to 60 million SWU per year if we want to become fully independent,” Liebenberg said. SWU stands for separative work unit, and it measures the amount of effort needed to enrich uranium.
In January 2026, the DOE announced $2.7 billion in task orders to restore American uranium enrichment over the next ten years.
Three generations of enrichment
Uranium was first enriched with gaseous diffusion during World War II. After 70 years, this was replaced by centrifuges, which are the standard today. This method involves spinning the uranium gas so that the lighter isotope moves towards the middle and the heavier one towards the outside of the centrifuge.
The third generation, which Liebenberg calls the “holy grail” of uranium enrichment, is laser enrichment. There are three different methods of laser enrichment. The first method is atomic vapor laser isotope separation (AVLIS). AVLIS was proven to work in the lab during the 1980s and 1990s, but no one has been able to scale it up.
The next method is a 16-micron MLIS-type (molecular laser isotope separation) laser approach, which involves a very complex laser system. Liebenberg worked on this method before moving into the 5-micron field, a much simpler method.
The basis of laser enrichment involves tuning the wavelength to selectively target uranium-235, leaving uranium-238 untouched.
A new enrichment method: CRISLA
LIS Technologies is developing a 5-micron laser enrichment method called CRISLA, which stands for condensation repression isotope selective laser activation. CRISLA uses the simpler 5-micron system borrowed from industrial and semiconductor manufacturing. Several researchers from LIS came from ASML, which makes advanced lithography systems for advanced micro semiconductor chips using industrial lasers.
CRISLA uses continuous wave (CW) lasers instead of the pulsed lasers used in other methods. In uranium enrichment, the gas has to be cold so that the two isotopes become distinct in their absorption bands. In order to chill the gas without condensing it, the gas is adiabatically expanded, which is when it goes through a supersonic nozzle similar to an aerosol can. The velocity of the expanded gas is up to 700 miles per hour. When the gas moves at this speed, a pulse laser only hits a fraction of the gas. In contrast, a CW laser is always on, hitting all of the gas.
In addition to a different laser method, CRISLA also uses a different harvesting method. Instead of batch harvesting, which requires the system to constantly start and stop, CRISLA uses continuous harvesting. This increases the efficiency of the enrichment process.
CRISLA can enrich uranium from its natural state, 0.7% uranium-235, to 5% in one step. With a centrifuge, that level of enrichment takes dozens of steps, Liebenberg explained. In two steps, the method can enrich uranium up to 20%, which is required for advanced reactors and microreactors.
The roadmap to commercialization
LIS Technologies has a four-phase roadmap to commercialize CRISLA. The first step is getting back to baseline, Liebenberg said. The company aims to repeat the results from the 1990s and to optimize the enrichment process. Simultaneously, phase two is to scale the process and demonstrate that the process works at an industrial scale. For this phase, the company is building its own next-generation lasers, Liebenberg said.
Phases one and two will take the company through 2028 at its test demonstration facility in Oak Ridge, Tennessee. Phases three and four move into commercialization. The first step was to find a site for a commercial facility, for which the company bought an island in Oak Ridge. The next steps are to prepare the site and to start the license application. By 2028, LIS Technologies will have the necessary license and facility to start phase four, which is production. By December 2029, the company will be ready for the pilot plan, and it will have a full production facility of 5 million SWU per year by the end of 2032, Liebenberg said.
“We will be the first company in the world to commercialize this in the next few years. We are the only U.S.-origin laser enrichment technology that exists,” said Liebenberg.
