BERKELEY, Calif., Mar. 28 -- Researchers at the US Department of Energy's Lawrence Berkeley National Laboratory have for the first time produced strobe-like flashes of synchrotron light lasting less than 300 fs off the primary beam of a synchrotron light source. The spectral range of these sub-picosecond pulses extended from infrared to x-ray wavelengths; the research team expects the technique to soon yield 100-fs pulse-lengths of x-rays. The scientists, working at the Advanced Light Source, extracted femtosecond pulses of synchrotron light directly from the electron beam in the synchrotron's storage ring. Since our approach creates a femtosecond time structure on the electron beam, standard radiating devices such as a bend-magnet, a wiggler, or an undulator, can be designed to emit femtosecond x-ray pulses with desired properties such as bandwidth, tunability, and brightness, said Robert Schoenlein, a physicist with the laboratory's Materials Sciences Division and senior author of a paper reporting this work in the journal Science.