Multiscale modeling of femtosecond laser irradiation on copper film with electron thermal conductivity from ab initio calculation

TL;DR

This paper develops a multiscale model integrating ab initio calculations of electron thermal conductivity to simulate femtosecond laser interactions with copper, revealing faster thermal diffusion and more extensive melting compared to empirical models.

Contribution

It introduces a novel multiscale modeling approach that incorporates ab initio derived electron thermal conductivity into laser-material interaction simulations.

Findings

Faster thermal diffusion with ab initio conductivity.

Deeper melting regions observed.

More diverse atomic cluster velocities during ablation.

Abstract

By combining ab initio quantum mechanics calculation and Drude model, electron temperature and lattice temperature dependent electron thermal conductivity is calculated and implemented into a multiscale model of laser material interaction, which couples the classical molecular dynamics and two-temperature model. The results indicated that the electron thermal conductivity obtained from ab initio calculation leads to faster thermal diffusion than that using the electron thermal conductivity from empirical determination, which further induces deeper melting region, larger number of density waves travelling inside the copper film and more various speeds of atomic clusters ablated from the irradiated film surface.