Manganese nanoclusters and nanowires on GaAs surfaces

TL;DR

This study investigates the magnetic properties of manganese clusters on GaAs surfaces, revealing significant magnetic moments and potential for spin-polarized channels, which could impact spintronic device development.

Contribution

It provides detailed calculations of magnetic moments and charge transfer for manganese on GaAs, highlighting the potential for spin-polarized nanowire channels.

Findings

Manganese exhibits a magnetic moment of 3.66 Bohr magnetons.

Arsenic's induced magnetic moment is two orders of magnitude smaller.

Charge transfer occurs from manganese to arsenic.

Abstract

We have computed the local magnetic moments of manganese and neighboring arsenic for various cluster configurations on the (001) surface of GaAs bulk crystal using a cluster of 512 atoms. We obtained for manganese a substantial local magnetic moment of 3.66 Bohr magnetons for all cases considered. The induced magnetic moment of arsenic is less than that of manganese by two orders of magnitude and falls off drastically beyond nearest neighbor distance. A small amount of charge is transferred from the manganese to arsenic. The possibility of a spin polarized wire channel on the arsenic layer below the surface is suggested.