[9p-N403-1~16] 7.2 Applications and technologies of electron beams

4:30 PM - 4:45 PM JST(7:30 AM - 7:45 AM UTC)Presentation by Applicant for JSAP Young Scientists Presentation Award

[9p-N403-12] Differences in propagation and properties of ultrashort pulsed electrons from tip and plate photocathode

〇(M1)Riyo Nagao¹, Gael Privault¹, Yusuke Arashida¹, Yui Iwasaki¹, Godai Noyama¹, Jun-ichi Fujita¹, Arnaud Arbouet^1,2, Masaki Hada¹ (1.Univ. Tsukuba, 2.CNRS IRL Dynacom)

Keywords:

Electron diffraction,Ultrafast phenomena

In this study, we performed numerical simulations to compare the characteristics of electron pulses generated from both tip and flat metal photocathodes. We found that a 1 μm-diameter tip photocathode can generate electron pulses with a transverse coherence length of ~10 nm under high-bunch-charge conditions, whereas conventional flat photocathodes yield only a few nanometers. These results demonstrate that tip photocathodes can maintain high coherence even in regimes where conventional designs are limited. Such enhanced coherence enables ultrafast structural dynamics studies of materials with periodicities in the 1–10 nm range, including proteins and nanoparticles, which are challenging to observe using conventional sources. Furthermore, these findings provide valuable insights for the development of novel electron sources in various probe-type electron microscopes, including transmission electron microscopes and scanning electron microscopes.