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arXiv · 0903.2587

Skyrmion Lattice in a Doped Semiconductor

W. Münzer·A. Neubauer·S. Mühlbauer·C. Franz·T. Adams·F. Jonietz·R. Georgii·P. Böni·B. Pedersen·M. Schmidt·A. Rosch·C. Pfleiderer
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Abstract

We report a comprehensive small angle neutron scattering study (SANS) of the magnetic phase diagram of the doped semiconductor Fe_{1-x}Co_{x}Si for x=0.2 and 0.25. For magnetic field parallel to the neutron beam we observe a six-fold intensity pattern under field-cooling, which identifies the A-phase of Fe_{1-x}Co_{x}Si as a skyrmion lattice. The regime of the skyrmion lattice is highly hysteretic and extents over a wide temperature range, consistent with the site disorder of the Fe and Co atoms. Our study identifies Fe_{1-x}Co_{x}Si is a second material after MnSi in which a skyrmion lattice forms and establishes that skyrmion lattices may also occur in strongly doped semiconductors.

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W. Münzer, A. Neubauer, S. Mühlbauer, C. Franz, T. Adams, F. Jonietz, R. Georgii, P. Böni, B. Pedersen, M. Schmidt, A. Rosch, C. Pfleiderer. 2009-03-16. Skyrmion Lattice in a Doped Semiconductor. https://doi.org/10.1103/physrevb.81.041203

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