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arXiv · 1611.08186

Defect-induced magnetism in SiC probed by nuclear magnetic resonance

Z. T. Zhang·D. Dmytriieva·S. Molatta·J. Wosnitza·Yutian Wang·M. Helm·Shengqiang Zhou·H. Kühne
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Abstract

We give evidence for intrinsic, defect-induced bulk paramagnetism in SiC by means of $^{13}$C and $^{29}$Si nuclear magnetic resonance (NMR) spectroscopy. The temperature dependence of the internal dipole-field distribution, probed by the spin part of the NMR Knight shift and the spectral linewidth, follows a Curie law and scales very well with the macroscopic DC susceptibility. In order to quantitatively analyze the NMR spectra, a microscopic model based on dipole-dipole interactions was developed. The very good agreement between these simulations and the NMR data establishes a direct relation between the frequency distribution of the spectral intensity and the corresponding real-space volumes of nuclear spins. The presented approach by NMR can be applied to a variety of similar materials and, thus, opens a new avenue for the microscopic exploration and exploitation of diluted bulk magnetism in semiconductors.

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Z. T. Zhang, D. Dmytriieva, S. Molatta, J. Wosnitza, Yutian Wang, M. Helm, Shengqiang Zhou, H. Kühne. 2017-03-12. Defect-induced magnetism in SiC probed by nuclear magnetic resonance. https://doi.org/10.1103/physrevb.95.085203

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