A new, all-optical method for compressing narrow electron pulses to a billionth of a billionth of a second could improve real-time movies of chemical reactions and other ultrafast processes.

An all-optical, 3D method of electron pulse compression for applications like ultrafast electron imaging is shown schematically in (a), with a cost-effective implementation depicted in (b). (Liang Jie Wong/Singapore Institute of Manufacturing Technology and Massachusetts Institute of Technology)

When the pulses hit the atoms in a material, the electrons scatter like a wave. By setting up a detector and analyzing the wave interference pattern, scientists can determine information like the distance between atoms. Short pulse durations are critical for high temporal resolution in ultrafast electron imaging techniques. These techniques can create movies that allow scientists to observe, in real-time, how molecules interact in a chemical reaction, or how the structure of a material or microorganism is affected by the introduction of external stimuli.