Influence of surface stoichiometry and quantum confinement on the electronic structure of small diameter InxGa1-xAs nanowires

TL;DR

This study uses density functional theory to analyze how surface chemistry, alloy composition, and quantum confinement influence the electronic properties of small InxGa1-xAs nanowires, highlighting factors crucial for nanoelectronic applications.

Contribution

It provides a detailed computational analysis of the combined effects of surface stoichiometry, alloy composition, and quantum confinement on InxGa1-xAs nanowires' electronic structure.

Findings

Surface chemistry significantly affects electronic properties.

Alloy stoichiometry impacts band gaps and effective masses.

Polar surfaces introduce notable electronic structure modifications.

Abstract

Electronic structures for InxGa1-xAs nanowires with [100], [110], and [111] orientations and critical dimensions of approximately 2 nm are treated within the framework of density functional theory. Explicit band structures are calculated and properties relevant to nanoelectronic design are extracted including band gaps, effective masses, and density of states. The properties of these III-V nanowires are compared to silicon nanowires of comparable dimensions as a reference system. In nonpolar semiconductors, quantum confinement and surface chemistry are known to play a key role in the determination of nanowire electronic structure. InxGa1-xAs nanowires have in addition effects due to alloy stoichiometry on the cation sublattice and due to the polar nature of the cleaved nanowire surfaces. The impact of these additional factors on the electronic structure for these polar semiconductor nanowires is shown to be significant and necessary for accurate treatment of electronic structure properties.