Electrodynamics - molecular dynamics simulations of the stability of Cu nanotips under high electric field

TL;DR

This study uses hybrid electrodynamics molecular dynamics simulations to demonstrate that high electric fields significantly enhance the stability of Cu nanotips, with implications for their use in high electric field applications.

Contribution

The paper introduces a simulation approach combining electrodynamics and molecular dynamics to analyze the stability of Cu nanotips under high electric fields, revealing the stabilizing effects of electric fields.

Findings

Electric fields of 1 GV/m increase nanotip stability

External electric fields stabilize tips more than field emission destabilizes

A new method detects critical reorientation temperature via crystal structure changes

Abstract

The shape memory effect and pseudoelasticity in Cu nanowires is one possible pair of mechanisms that prevents high aspect ratio nanosized field electron emitters to be stable at room temperature and permits their growth under high electric field. By utilizing hybrid electrodynamics molecular dynamics simulations we show that a global electric field of 1 GV/m or more significantly increases the stability and critical temperature of spontaneous reorientation of nanosized <100> Cu field emitters. We also show that in the studied tips the stabilizing effect of an external applied electric field is an order of magnitude greater than the destabilization caused by the field emission current. We detect the critical temperature of spontaneous reorientation using the tool that spots the changes in crystal structure. The method is compatible with techniques that consider the change in potential energy, has a wider range of applicability and allows pinpointing different stages in the reorientation processes.