Collinear and non-collinear spin ground state of wurtzite CoO

TL;DR

This study uses first-principles calculations to explore the spin structures of wurtzite CoO, revealing a stable antiferromagnetic order and a possible non-collinear spiral spin state influenced by spin-orbit coupling, relevant for nano-magnetism.

Contribution

It identifies the most stable collinear and non-collinear spin configurations of wurtzite CoO, highlighting the potential for non-collinear spin ground states in nanostructures.

Findings

AF3-type antiferromagnetic order is most stable among collinear configurations

A spiral non-collinear spin order can be stabilized with spin-orbit coupling

Non-collinear spin ground states may be observed in transition-metal-oxide nanostructures

Abstract

Collinear and non-collinear spin structures of wurtzite phase CoO often appearing in nano-sized samples are investigated using first-principles density functional theory calculations. We examined the total energy of several different spin configurations, electronic structure and the effective magnetic coupling strengths. It is shown that the AF3-type antiferromagnetic ordering is energetically most stable among possible collinear configurations. Further, we found that a novel spiral spin order can be stabilized by including the relativistic spin-orbit coupling and the non-collinearity of spin direction. Our result suggests that a non-collinear spin ground state can be observed in the transition-metal-oxide nanostructures which adds an interesting new aspect to the nano-magnetism study.