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arXiv · 1103.4917

Effect of co-doping of donor and acceptor impurities in the ferromagnetic semiconductor Zn1-xCrxTe studied by soft x-ray magnetic circular dichroism

Y. Yamazaki·T. Kataoka·V. R. Singh·A. Fujimori·F. -H. Chang·D. -J. Huang·H. -J. Lin·C. T. Chen·K. Ishikawa·K. Zhang·S. Kuroda
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Abstract

We have performed x-ray absorption spectroscopy (XAS) and x-ray magnetic circular dichroism (XMCD) studies of the diluted ferromagnetic semiconductor Zn$_{1-\textit{x}}$Cr$_\textit{x}$Te doped with iodine (I) or nitrogen (N), corresponding to electron or hole doping, respectively. From the shape of the Cr $2p$ absorption peak in the XAS spectra, it was concluded that Cr ions in the undoped, I-doped and lightly N-doped samples are divalent (Cr$^{2+}$), while Cr$^{2+}$ and trivalent (Cr$^{3+}$) coexist in the heavily N-doped sample. This result indicates that the doped nitrogen atoms act as acceptors but that doped holes are located on the Cr ions. In the magnetic-field dependence of the XMCD signal at the Cr $2p$ absorption edge, ferromagnetic behaviors were observed in the undoped, I-doped, and lightly N-doped samples, while ferromagnetism was considerably suppressed in heavily N-doped sample, which is consistent with the results of magnetization measurements.

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Y. Yamazaki, T. Kataoka, V. R. Singh, A. Fujimori, F. -H. Chang, D. -J. Huang, H. -J. Lin, C. T. Chen, K. Ishikawa, K. Zhang, S. Kuroda. 2011-03-25. Effect of co-doping of donor and acceptor impurities in the ferromagnetic semiconductor Zn1-xCrxTe studied by soft x-ray magnetic circular dichroism. https://doi.org/10.1088/0953-8984%2F23%2F17%2F176002

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