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arXiv · 1104.0197

Spin waves cause non-linear friction

Martin P. Magiera·Lothar Brendel·Dietrich E. Wolf·Ulrich Nowak
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Abstract

Energy dissipation is studied for a hard magnetic tip that scans a soft magnetic substrate. The dynamics of the atomic moments are simulated by solving the Landau-Lifshitz-Gilbert (LLG) equation numerically. The local energy currents are analysed for the case of a Heisenberg spin chain taken as substrate. This leads to an explanation for the velocity dependence of the friction force: The non-linear contribution for high velocities can be attributed to a spin wave front pushed by the tip along the substrate.

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Martin P. Magiera, Lothar Brendel, Dietrich E. Wolf, Ulrich Nowak. 2011-06-24. Spin waves cause non-linear friction. https://doi.org/10.1209/0295-5075%2F95%2F17010

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