Extraction dynamics of electrons from magneto-optically trapped atoms

作者：Fedchenko Olena^*; Chernov Sergii; McCulloch Andrew; Vielle Grosjean Melissa; Comparat Daniel; Schoenhense Gerd

来源：Applied Physics Letters, 2017, 111(2): 021104.

DOI：10.1063/1.4991366

Pulsed photoionization of laser-cooled atoms in a magneto-optical trap (MOT) has the potential to create cold electron beams of few meV bandwidths and few ps pulse lengths. Such a source would be highly attractive for the study of fast low-energy processes like coherent phonon excitation. To study the suitability of MOT-based sources for the production of simultaneously cold and fast electrons, we study the photoionization dynamics of trapped Cs atoms. A momentum-microscope-like setup with a delay-line detector allows for the simultaneous measurement of spatial and temporal electron distributions. The measured patterns are complex, due to the Lorentz force inducing spiral trajectories. Ray-tracing simulations reproduce the main features. We find that the production of electron bunches with bandwidths of a few meV is straightforward; however, pulses in the ps-range are more demanding and require beam blanking or partial blocking. Published by AIP Publishing.

• 出版日期2017-7-10