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arXiv · 0708.2217

Ferromagnetism in cobalt doped n-GaN

S. Dhara·B. Sundaravel·K. G. M. Nair·R. Kesavamoorthy·M. C. Valsakumar·T. V. Chandrasekhar Rao·L. C. Chen·K. H. Chen
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Abstract

Ferromagnetic ordering is reported in the post-annealed samples of Co doped n-GaN formed by Co+ implantation. A maximum Curie temperature ~ 250K is recorded for the sample with 8 atomic percent Co. Particle induced x-ray emission-channeling study confirmed the substitutional Co in Ga lattice site. Local atomic arrangement around magnetic impurities is also analyzed using Raman study. A disordered model with carrier mediated coupling of localized magnetic moments is made responsible for the observed ferromagnetic ordering.

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S. Dhara, B. Sundaravel, K. G. M. Nair, R. Kesavamoorthy, M. C. Valsakumar, T. V. Chandrasekhar Rao, L. C. Chen, K. H. Chen. 2007-08-16. Ferromagnetism in cobalt doped n-GaN. https://doi.org/10.1063/1.2194347

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