Speaker
Description
In the presence of strong electric fields, a plasma-induced arc of intense current is capable of establishing a connection between two metal surfaces, even within the confines of ultra-high vacuum conditions. According to the hypothesis, the presence of tall and sharp nanotips on a surface exposed to strong electric fields undergoes heating via field emission currents, ultimately resulting in melting and the evaporation of neutral atoms contributing to plasma buildup. However, the mechanism governing the growth of nanotips with a significantly high aspect ratio remains unclear. Previous experimental research has demonstrated that the application of a thin carbon film on a metallic surface enhances the rate of vacuum arc events.
This study employs the Nudged Elastic Band method to systematically investigate the migration barrier of various carbon structures onto diamond, amorphous carbon, graphite and graphene surfaces. The primary objective is to estimate the probability of carbon surface diffusion, specifically considering the influence of an electric field gradient. The investigation aims to discern whether carbon surface diffusion, biased by the presence of such a gradient, can facilitate the transport of atoms, ultimately leading to the formation of nanotips.
Keywords:
Nudged Elastic Band, Migration Barriers, Surface Diffusion, Carbon, Amorphous Carbon, Diamond, Graphite, Graphene, Vacuum Arc, Nanotip
