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Carbon p electron ferromagnetism in silicon carbide.

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.

SUBMITTER: Wang Y

PROVIDER: S-EPMC4355737 | biostudies-literature | 2015 Mar

REPOSITORIES: biostudies-literature

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Carbon p electron ferromagnetism in silicon carbide.

Wang Yutian Y Liu Yu Y Wang Gang G Anwand Wolfgang W Jenkins Catherine A CA Arenholz Elke E Munnik Frans F Gordan Ovidiu D OD Salvan Georgeta G Zahn Dietrich R T DR Chen Xiaolong X Gemming Sibylle S Helm Manfred M Zhou Shengqiang S

Scientific reports 20150311

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 divaca ...[more]

PMID: 25758040

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