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arXiv · 1305.6496

Collinear and non-collinear spin ground state of wurtzite CoO

Myung Joon Han·Heung-Sik Kim·Dong Geun Kim·Jaejun Yu
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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.

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Myung Joon Han, Heung-Sik Kim, Dong Geun Kim, Jaejun Yu. 2013-05-27. Collinear and non-collinear spin ground state of wurtzite CoO. https://doi.org/10.1103/physrevb.87.184432

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