Abstract
We present the first observation of subpicosecond electron bunches from an ultracold electron source. This source is based on near-threshold, two-step, femtosecond photoionization of laser-cooled rubidium gas in a grating magneto-optical trap. Bunch lengths as short as 735±7 fs (rms) have been measured in the self-compression point of the source by means of ponderomotive scattering of the electrons by a 25 fs, 800 nm laser pulse. The observed temporal structure of the electron bunch depends on the central wavelength of the ionization laser pulse, in agreement with detailed simulations of the atomic photoionization process. This shows that the bunch length limit imposed by the atomic photoionization process has been reached.
| Original language | English |
|---|---|
| Article number | 205001 |
| Number of pages | 7 |
| Journal | Physical Review Letters |
| Volume | 130 |
| Issue number | 20 |
| DOIs | |
| Publication status | Published - 19 May 2023 |
Bibliographical note
Publisher Copyright:© 2023 authors. Published by the American Physical Society. Published by the American Physical Society under the terms of the "https://creativecommons.org/licenses/by/4.0/"Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.
Funding
The authors would like to thank Harry van Doorn and Eddy Rietman for their expert technical assistance. The grating was supplied by the Strathclyde grating MOT team. This publication is part of the Industrial Partnership Program ColdLight which is financed by the Dutch Research Council (NWO) and the Dutch company Acctec B.V.