An article published in the new issue of Science & Global Security, "A Proliferation Assessment of Third Generation Laser Uranium Enrichment Technology," (Free PDF) by Ryan Snyder, provides a detailed analysis of the physical principles and operationalization of uranium isotope separation through laser excitation and preferential condensation repression of uranium-235 hexafluoride. The SILEX (Separation of Isotopes by Laser Excitation) system that was licensed for commercialization in the United States by General Electric, Hitachi, and Cameco as the Global Laser Enrichment project may be based on such a mechanism.
The article provides a model laser enrichment cascade able to produce enough weapon-grade highly enriched uranium (90 percent uranium-235) for at least one weapon per year, and a preliminary assessment of key associated signatures--the physical space, energy consumption and technical skills required for such a cascade--suggesting that these may be less than for an analogous centrifuge-based set-up. Lasers that could be used in such a system are described in an online supplement that also details aspects of the enrichment mechanism, associated enrichment factor (which may be significantly larger than for centrifuges) and cascade model. The results highlight the need for a formal public proliferation assessment of laser enrichment technologies such as SILEX and the Global Laser Enrichment project with access to actual design information and key operating parameters and signatures.