Development of the temperature-dependent interatomic potential for molecular dynamics simulation of metal irradiated with an ultrashort pulse laser

TL;DR

This paper introduces a temperature-dependent interatomic potential for molecular dynamics simulations of metals under ultrashort laser pulses, enabling more accurate modeling of laser-material interactions.

Contribution

The authors extend the embedded atom method to include electron temperature dependence, allowing classical MD simulations to incorporate two-temperature model effects.

Findings

The potential accurately reproduces physical properties like energy-volume curves and phonon dispersion.

It matches finite-temperature DFT results for electronic heat capacity.

Demonstrates validity through comparison with experimental ablation thresholds.

Abstract

Laser ablation is often explained by a two-temperature model (TTM) with different electron and lattice temperatures. To realize a classical molecular dynamics simulation of the TTM, we propose an extension of the embedded atom method to construct an interatomic potential that is dependent on the electron temperature. This method is applied to copper, and its validity is demonstrated by comparison of several physical properties, such as the energy-volume curve, phonon dispersion, electronic heat capacity, ablation threshold, and mean square displacement of atoms, with those of finite-temperature density functional theory.