Free-Electron Laser Achieves 10 kW in the Infrared

Scientists at the Thomas Jefferson National Accelerator Facility in Newport News, Va., have produced 10 kW of tunable infrared radiation from their free-electron laser. The laser is of interest to the US Navy for potential shipboard directed-energy defense systems and to researchers for use in the investigation of phenomena in the physical and biological sciences.

The instrument began life as a 1-kW demonstration project and went on to produce 2.1 kW of IR radiation before it was taken offline in 2001 for an upgrade. The improved device, which incorporates a superconducting energy-recovering linear accelerator, achieved first light last summer. Accelerated electrons are injected into a wiggler magnet, where they are induced to emit photons. The scientists can tune the wavelength of the radiation between 1 and 14 µm by changing the energies of the electrons in the accelerator or the properties of the magnetic field in the wiggler.

The Navy hopes to apply lessons learned from the work toward the development of a 100-kW free-electron laser in the next four years, with the goal of eventually achieving megawatt power levels.