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arXiv · 1503.00487

Carbon p Electron Ferromagnetism in Silicon Carbide

Y. Wang·Y. Liu·G. Wang·W. Anwand·C. Jenkins·E. Arenholz·F. Munnik·O. Gordan·G. Salvan·D. R. T. Zahn·X. Chen·S. Gemming·M. Helm·S. Zhou
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Abstract

Ferromagnetism can occur in wide-band gap semiconductors as well as in carbon-based materials when specific defects are introduced. It is thus desirable to establish a direct relation between the defects and the resulting ferromagnetism. Here, we contribute to revealing the origin of defect-induced ferromagnetism using SiC as a prototypical example. We show that the long-range ferromagnetic coupling can be attributed to the p electrons of the nearest-neighbor carbon atoms around the VSiVC divacancies. Thus, the ferromagnetism is traced down to its microscopic, electronic origin.

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Y. Wang, Y. Liu, G. Wang, W. Anwand, C. Jenkins, E. Arenholz, F. Munnik, O. Gordan, G. Salvan, D. R. T. Zahn, X. Chen, S. Gemming, M. Helm, S. Zhou. 2015-03-02. Carbon p Electron Ferromagnetism in Silicon Carbide. https://doi.org/10.1038/srep08999

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