Spin waves cause non-linear friction
Faculty of Physics and CeNIDE, University of Duisburg-Essen - D-47048 Duisburg, Germany, EU
2 Department of Physics, University of Konstanz - D-78457 Konstanz, Germany, EU
Accepted: 23 May 2011
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.
PACS: 75.10.Hk – Classical spin models / 68.35.Af – Atomic scale friction / 75.30.Ds – Spin waves
© EPLA, 2011