Physicists break record for laser-electron interaction

Researchers have converted the energy of an electron beam into a pulse of coherent light with an efficiency of 30% – much higher than the 10% efficiency of most free-electron lasers. While their demonstration produces only infrared light, the method could lead to efficient, high-power lasers operating over a range of wavelengths, including X-ray. Such X-ray sources could be used to etch circuits on semiconductor chips faster and more efficiently.