Modified Li chains as atomic switches

TL;DR

This paper investigates how impurities affect the electronic transport properties of hydrogen and lithium atomic chains, revealing conditions for switching between metallic and insulating states using density functional theory and scattering theory.

Contribution

It systematically studies impurity effects on atomic chain conductance, providing insights into impurity-induced level splitting and switching mechanisms.

Findings

Impurities can induce level splitting in atomic chains.

Certain impurities enable switching between metallic and insulating states.

Electronegative impurities significantly alter transport properties.

Abstract

We present electronic structure and transport calculations for hydrogen and lithium chains, using density functional theory and scattering theory on the Green's function level, to systematically study impurity effects on the transmission coefficient. To this end we address various impurity configurations. Tight-binding results allow us to interpret our the findings. We analyze under which circumstances impurities lead to level splitting and/or can be used to switch between metallic and insulating states. We also address the effects of strongly electronegative impurities.