2024/09/30 by Marciniak, Wojciech, Marciniak, Joanna, Castellanos-Reyes, José Ángel +1
#Computational Physics (physics.comp-ph) #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Statistical Mechanics (cond-mat.stat-mech)
paper · doi:10.48550/arxiv.2409.20334
We present a computational method and apply it to study phonon relaxation in face-centered cubic (fcc) nickel (Ni). The phonons are excited beyond their thermal equilibrium population, and the relaxation behavior is analyzed as a function of both the wave vector q and the phonon frequency ω. To efficiently investigate these excitations, we introduce a trajectory post-processing technique, the frozen-trajectory excitation, which facilitates the (q,ω)-resolved analysis. Molecular dynamics simulations combined with frozen-phonon multislice calculations predict relaxation signatures observable with time-resolved transmission electron microscopy (TEM) at 10--20 fs resolution. Our findings indicate mode dependence in the relaxation processes, highlighting the importance of considering phonon-specific behavior in ultrafast dynamics.