Nonlinear current-induced forces in Si atomic wires

TL;DR

This paper presents first-principles calculations showing that current-induced forces in silicon atomic wires are highly nonlinear with bias and depend on wire length, impacting their mechanical stability under current.

Contribution

It introduces a detailed analysis of nonlinear current-induced forces in Si atomic wires, highlighting the dependence on bias and wire length, supported by first-principles calculations.

Findings

Forces are strongly nonlinear with bias.

Shorter wires experience larger average forces.

Longer wires are more resistant to breaking under current.

Abstract

We report first-principles calculations of current-induced forces in Si atomic wires as a function of bias and wire length. We find that these forces are strongly nonlinear as a function of bias due to the competition between the force originating from the scattering states and the force due to bound states. We also find that the average force in the wire is larger the shorter the wire, suggesting that atomic wires are more difficult to break under current flow with increasing length. The last finding is in agreement with recent experimental data.