Formation of atom wires on vicinal silicon

TL;DR

This study investigates the formation of gallium atomic wires on vicinal silicon surfaces, revealing that zig-zag chains are favored over linear chains and that the surface exhibits non-metallic, quasi-one-dimensional properties.

Contribution

It combines experimental STM data and DFT calculations to analyze candidate structures, concluding that Ga zig-zag chains are the preferred formation on Si(112).

Findings

Ga zig-zag chains are favored over linear chains.

The surface is non-metallic with quasi-one-dimensional conduction.

Formation occurs under both equilibrium and non-equilibrium conditions.

Abstract

The formation of atomic wires via pseudomorphic step-edge decoration on vicinal silicon surfaces has been analyzed for Ga on the Si(112) surface using Scanning Tunneling Microscopy and Density Functional Theory calculations. Based on a chemical potential analysis involving more than thirty candidate structures and considering various fabrication procedures, it is concluded that pseudomorphic growth on stepped Si(112), both under equilibrium and non-equilibrium conditions, must favor formation of Ga zig-zag chains rather than linear atom chains. The surface is non-metallic and presents quasi-one dimensional character in the lowest conduction band.