Free-Electron Laser Passes 1-kW Goal

For tunability and high power in short-wave-length light, few lasers can compete with free-electron technology. Recent research has raised the bar. Scientists at the Thomas Jefferson National Accelerator Facility in Newport News, Va., reported that their free-electron laser reached 1.7-kW performance at 3.1 m. The laser's achievement exceeded its 1-kW goal; the next goal is 10 kW of continuous-wave output in the infrared.

Contributing to the accomplishment was the linear accelerator, which helped boost energy recovery to 75 percent. The laser recycles power from the electron beam that is not radiated as light and re-emits it to achieve the equivalent of 10 percent conversion efficiency.