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arXiv · 0802.1313

Oxygen Vacancy Induced Ferromagnetism in V$_2$O$_{5-x}$

Zhi Ren Xiao·Guang Yu Guo·Po Han Lee·Hua Shu Hsu·Jung Chun Andrew Huang
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Abstract

{\it Ab initio} calculations within density functional theory with generalized gradient approximation have been performed to study the effects of oxygen vacancies on the electronic structure and magnetism in undoped V$_2$O$_{5-x}$ ($0 < x < 0.5$). It is found that the introduction of oxygen vacancies would induce ferromagnetism in V$_2$O$_{5-x}$ with the magnetization being proportional to the O vacancy concentration $x$. The calculated electronic structure reveals that the valence electrons released by the introduction of oxygen vacancies would occupy mainly the neighboring V $d_{xy}$-dominant band which then becomes spin-polarized due to intra-atomic exchange interaction, thereby giving rise to the half-metallic ferromagnetism.

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Zhi Ren Xiao, Guang Yu Guo, Po Han Lee, Hua Shu Hsu, Jung Chun Andrew Huang. 2008-02-10. Oxygen Vacancy Induced Ferromagnetism in V$_2$O$_{5-x}$. https://arxiv.org/abs/0802.1313

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