The development of table-top femtosecond electron diffraction sources in recent years has opened up a new way to observe atomic motions in crystalline materials undergoing structural changes. Here, the technique is used to study the charge density wave material 1T-TaS2, where a modulation of the electron density is accompanied by a periodic lattice distortion. In this femtosecond electron diffraction experiment, where atomic motions are observed in response to a 140 femtosecond optical pulse, the periodic lattice distortion is found to collapse on an exceptionally fast timescale (about 250 femtoseconds), indicative of an electronically driven process involving a highly cooperative process.
- Maximilian Eichberger
- Hanjo Schäfer
- R. J. Dwayne Miller