Coupled simulation of plasma-surface interactions during early stages of vacuum arcing

Researchers have developed fully coupled simulations that integrate atomistic cathode dynamics with plasma formation during the initial phases of vacuum arcing. The model links molecular dynamics, finite element electrothermal calculations, electron emission, and particle-in-cell plasma simulations.

These simulations dynamically transfer particles between surface and plasma domains, providing a comprehensive view of the arcing process. The study specifically examined copper nanoprotrusions to understand the underlying mechanisms.

The findings identified two routes to thermal runaway: one driven by direct Joule heating and a newly discovered nanoparticle-assisted mechanism. In the latter, detached nanoparticles create neutral vapor that subsequently ionizes, contributing to the instability.