With the development of ultrafast electron and x-ray sources it is becoming possible to study structural dynamics with atomic-level spatial and temporal resolution (i.e. 0.1 nm and 0.1 ps). Because of their short mean free path, electrons are well suited for investigating thin films, such as protein membranes. However, current electron sources have insufficient intensity or coherence to perform single-shot experiments on protein crystals. We developed an ultracold electron source, based on near-threshold photoionization of laser-cooled atoms, for producing pulses of high intensity and high coherence. We show that high coherence electron pulses can be produced by femtosecond photoionization, opening up a new regime of single-shot ultrafast structural dynamics experiments. The transverse coherence turns out to be much better than expected on the basis of the large bandwidth of the femtosecond ionization laser. This result can be explained by analysis of classical electron trajectories.
|Title of host publication||Presentation at the Physics@FOM Veldhoven, 22-23 januari 2013, Veldhoven, The Netherlands|
|Place of Publication||Utrecht|
|Publication status||Published - 2013|
|Event||Physics@FOM Veldhoven 2013 - Koningshof, Veldhoven, Netherlands|
Duration: 22 Jan 2013 → 23 Jan 2013
|Conference||Physics@FOM Veldhoven 2013|
|Period||22/01/13 → 23/01/13|