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arXiv · 0908.2906

MnSi$_{1.7}$ nanoparticles embedded in Si: Superparamagnetism with a collective behavior

Shengqiang Zhou·A. Shalimov·K. Potzger·M. Helm·J. Fassbender·H. Schmidt
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Abstract

The doping of Mn in Si is attracting research attentions due to the possibility to fabricate Si-based diluted magnetic semiconductors. However, the low solubility of Mn in Si favors the precipitation of Mn ions even at non-equilibrium growth conditions. MnSi$_{1.7}$ nanoparticles are the common precipitates, which show exotic magnetic properties in comparison with the MnSi$_{1.7}$ bulk phase. In this paper we present the static and dynamic magnetic properties of MnSi$_{1.7}$ nanoparticles. Using the Preisach model, we derive the magnetic parameters, such as the magnetization of individual particles, the distribution of coercive fields and the inter-particle interaction field. Time-dependent magnetization measurements reveal a spin-glass behavior of the system.

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Shengqiang Zhou, A. Shalimov, K. Potzger, M. Helm, J. Fassbender, H. Schmidt. 2009-08-20. MnSi$_{1.7}$ nanoparticles embedded in Si: Superparamagnetism with a collective behavior. https://doi.org/10.1103/physrevb.80.174423

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