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arXiv · 1201.0006

Ferromagnetism in ZnO co-doped with Mn and N studied by soft x-ray magnetic circular dichroism

T. Kataoka·Y. Yamazaki·V. R. Singh·Y. Sakamoto·A. Fujimori·Y. Takeda·T. Ohkochi·S. -I. Fujimori·T. Okane·Y. Saitoh·H. Yamagami·A. Tanaka·M. Kapilashrami·L. Belova·K. V. Rao
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Abstract

We have investigated the electronic structure of ZnO:Mn and ZnO:Mn,N thin films using x-ray magnetic circular dichroism (XMCD) and resonance-photoemission spectroscopy. From the Mn 2$p$$\rightarrow3d$ XMCD results, it is shown that, while XMCD signals only due to paramagnetic Mn$^{2+}$ ions were observed in ZnO:Mn, nonmagnetic, paramagnetic and ferromagnetic Mn$^{2+}$ ions coexist in ZnO:Mn,N. XMCD signals of ZnO:Mn,N revealed that the localized Mn$^{2+}$ ground state and Mn$^{2+}$ state hybridized with ligand hole coexisted, implying $p$-$d$ exchange coupling. In the valence-band spectra, spectral weight near the Fermi level was suppressed, suggesting that interaction between magnetic moments in ZnO:Mn,N has localized nature.

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T. Kataoka, Y. Yamazaki, V. R. Singh, Y. Sakamoto, A. Fujimori, Y. Takeda, T. Ohkochi, S. -I. Fujimori, T. Okane, Y. Saitoh, H. Yamagami, A. Tanaka, M. Kapilashrami, L. Belova, K. V. Rao. 2011-12-28. Ferromagnetism in ZnO co-doped with Mn and N studied by soft x-ray magnetic circular dichroism. https://doi.org/10.1063/1.3643044

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