Structures and magnetic properties of ZnO nanoislands

TL;DR

This study uses first-principles calculations to explore the atomic structures and magnetic properties of two-dimensional ZnO nanoislands, revealing edge-dependent magnetism and size effects on magnetic moments.

Contribution

It provides new insights into the magnetic behavior of ZnO nanoislands, especially the edge-induced magnetism in monolayer structures, which was not previously characterized.

Findings

Monolayer ZnO nanoisland with O-terminated zigzag edges is magnetic.

Other nanoislands are nonmagnetic at their ground states.

Larger nanoislands exhibit larger magnetic moments.

Abstract

Using first-principles calculations, we systematically study the atomic structures and electronic properties for two dimensional triangular ZnO nanoislands that are graphite-like with monolayer and bilayer thickness. We find that the monolayer ZnO nanoisland with O terminated zigzag edges is magnetic at its ground state, with the magnetism coming from the O edge states. The other monolayer and bilayer ZnO nanoislands with different edge structures are all nonmagnetic at their ground states. It is further revealed that for different ZnO nanoislands, their magnetic properties are quite dependent on their sizes, with larger nanoislands having larger magnetic moments.