Development of a high brightness ultrafast Transmission Electron Microscope based on a laser-driven cold field emission source

Florent Houdellier (1) , Giuseppe Mario Caruso (2) , Sébastien J. Weber (2) , M. Kociak (3) , Arnaud Arbouet (4)

1 CEMES-I3EM - Interférométrie, In situ et Instrumentation pour la Microscopie Electronique
2 CEMES - Centre d'élaboration de matériaux et d'études structurales
3 LPS - Laboratoire de Physique des Solides
4 CEMES-NeO - Nano-Optique et Nanomatériaux pour l'optique

We report on the development of an ultrafast Transmission Electron Microscope based on a cold field emission source which can operate in either DC or ultrafast mode. Electron emission from a tungsten nanotip is triggered by femtosecond laser pulses which are tightly focused by optical components integrated inside a cold field emission source close to the cathode. The properties of the electron probe (brightness, angular current density, stability) are quantitatively determined. The measured brightness is the largest reported so far for UTEMs. Examples of imaging, diffraction and spectroscopy using ultrashort electron pulses are given. Finally, the potential of this instrument is illustrated by performing electron holography in the off-axis configuration using ultrashort electron pulses.

Mots clés: Ultrafast Transmission Electron Microscopy; Field emission; Nanoemitters; Electron interferometry

Domaines: Matériaux; Optique / photonique; Traitement du signal et de l'image [eess.SP]; Electromagnétisme; Physique des accélérateurs [physics.acc-ph]; Physique Quantique [quant-ph]; Physique des Hautes Energies - Expérience [hep-ex]; Optique [physics.optics]

Florent Houdellier, Giuseppe Mario Caruso, Sébastien J. Weber, M. Kociak, Arnaud Arbouet. Development of a high brightness ultrafast Transmission Electron Microscope based on a laser-driven cold field emission source. Ultramicroscopy, 2018, 186, pp.128 - 138. ⟨10.1016/j.ultramic.2017.12.015⟩. ⟨hal-01846146⟩