On the Study of Electron-Phonon and Phonon-Phonon Coupling in Femtosecond Laser-Excited Tungsten

Understanding the dynamics of electron-phonon and phonon-phonon interactions is important to unravel the complex behavior of materials subject to ultrafast laser excitation. We report the results of studying these interactions in femtosecond laser-excited tungsten (W) using the technique of ultrafast electron diffuse scattering (UEDS). By tracking changes of diffuse scattering signal over time, we resolve the dynamics of phonon populations across the Brillouin zone in W. Our results shed light on both electron-phonon and phonon-phonon coupling dynamics in W [Mo et al. Science Advances 10, eadk9051 (2024)]. This paper outlines the fundamental principle behind the UEDS technique, provides a brief overview of the experimental setup, and presents selected results of time-resolved diffuse scattering patterns.