In trials at Duke University in Durham, N.C., a Russian-built tunable ultraviolet free-electron laser achieved 226 nm, a milestone that could portend uses in a variety of medical and physical science experiments. Known as the OK-4 optical klystron, the laser emits in the deep-UV. Previously, the optical klystron laser achieved a 240-nm wavelength mark, set at Budker Institute of Nuclear Physics in Novosibirsk, Russia, in October 1988. In free-electron lasers, electrons are liberated from their original atoms and emit an increased number of discrete wavelengths. Scientists hope the OK-4 will provide UV light in eye surgery, neurosurgery and cancer research.