# Solid-to-super Critical Phase Change during Laser Internal Ablation

## TL;DR

This study uses molecular dynamics simulations to explore the complex phase change process of argon during picosecond laser internal ablation, revealing a cyclic transition from solid to supercritical fluid and back.

## Contribution

It uncovers the detailed mechanisms of phase transitions in argon under laser ablation, highlighting the roles of stress waves and temperature fluctuations.

## Key findings

- Phase change involves solid, liquid, supercritical fluid, and back to solid.
- Stress wave propagation influences phase transition dynamics.
- Temperature fluctuations are periodic during ablation.

## Abstract

The mechanisms of phase change of argon during picosecond laser internal ablation are studied using molecular dynamics simulations. It is found that propagation of stress wave and fluctuation of temperature are periodical. The phase change process from solid to liquid to supercritical fluid then back to solid occurs as combined results of heating and the propagation of tensile stress wave induced by the laser pulse and the limited internal space.

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Source: https://tomesphere.com/paper/1702.04079