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arXiv · 1007.0269

ZnO:Co Diluted Magnetic Semiconductor or Hybrid Nanostructure for Spintronics?

F. Golmar·M. Villafuerte·A. Mudarra Navarro·C. E. Rodrıguez Torres·J. Barzola-Quiquia·P. Esquinazi·S. P. Heluani
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Abstract

We have studied the influence of intrinsic and extrinsic defects in the magnetic and electrical transport properties of Co-doped ZnO thin films. X ray absorption measurements show that Co substitute Zn in the ZnO structure and it is in the 2+ oxidation state. Magnetization (M) measurements show that doped samples are mainly paramagnetic. From M vs. H loops measured at 5 K we found that the values of the orbital L and spin S numbers are between 1 and 1.3 for L and S = 3/2, in agreement with the representative values for isolated Co 2+. The obtained negative values of the Curie-Weiss temperatures indicate the existence of antiferromagnetic interactions between transition metal atoms.

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F. Golmar, M. Villafuerte, A. Mudarra Navarro, C. E. Rodrıguez Torres, J. Barzola-Quiquia, P. Esquinazi, S. P. Heluani. 2010-07-01. ZnO:Co Diluted Magnetic Semiconductor or Hybrid Nanostructure for Spintronics?. https://doi.org/10.1007/s10853-010-4710-2

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