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arXiv · 1305.5196

Discrete helicoidal states in chiral magnetic thin films

M. N. Wilson·E. A. Karhu·D. P. Lake·A. S. Quigley·A. N. Bogdanov·U. K. Rößler·T. L. Monchesky
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Abstract

Magnetometry and magnetoresistance measurements in MnSi thin films and rigorous analytical solutions of the micromagnetic equations show that the field-induced unwinding of confined helicoids occurs via discrete steps. A comparison between the magnetometry data and theoretical results shows that finite size effects confine the wavelength and lead to a quantization of the number of turns in the helicoid. We demonstrate a prototypical spintronic device where the magnetic field can push or pull individual turns into a magnetic spring that can be read by electrical means.

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M. N. Wilson, E. A. Karhu, D. P. Lake, A. S. Quigley, A. N. Bogdanov, U. K. Rößler, T. L. Monchesky. 2014-02-25. Discrete helicoidal states in chiral magnetic thin films. https://doi.org/10.1103/physrevb.88.214420

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