アト秒電子パルスの発生と電子回折への応用

抄録

Electron diffraction has been a powerful tool to investigate atomistic structures of molecules, liquids, and solids. Time-resolved diffraction with pulsed electron beams is capable of visualizing transient structural changes with the combined fast temporal and atomic-scale spatial resolutions. Considerable effort has been devoted to producing ultrashort electron pulses for the imaging of atomic and electronic motions occurring on the time scale of femtoseconds and attoseconds, respectively. This account briefly describes technologies for producing ultrashort electron pulses including our recent works where we produced and detected attosecond electron pulses by manipulating electron beams with laser light. A qualitative discussion is given on the modulation of a diffraction pattern due to a change of electron density distribution in a molecule. Electron diffraction with attosecond pulses will allow to visualize how electron clouds in a molecule or material evolve in space and time during a reaction.