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arXiv · 1001.2682

Control of the chirality and polarity of magnetic vortices in triangular nanodots

M. Jaafar·R. Yanes·D. Perez de Lara·O. Chubykalo-Fesenko·A. Asenjo·E. M. Gonzalez·J. V. Anguita·M. Vazquez·J. L. Vicent
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Abstract

Magnetic vortex dynamics in lithographically prepared nanodots is currently a subject of intensive research, particularly after recent demonstration that the vortex polarity can be controlled by in-plane magnetic field. This has stimulated the proposals of non-volatile vortex magnetic random access memories. In this work, we demonstrate that triangular nanodots offer a real alternative where vortex chirality, in addition to polarity, can be controlled. In the static regime, we show that vortex chirality can be tailored by applying in-plane magnetic field, which is experimentally imaged by means of Variable-Field Magnetic Force Microscopy. In addition, the polarity can be also controlled by applying a suitable out-of-plane magnetic field component. The experiment and simulations show that to control the vortex polarity, the out-of-plane field component, in this particular case, should be higher than the in-plane nucleation field. Micromagnetic simulations in the dynamical regime show that the magnetic vortex polarity can be changed with short-duration magnetic field pulses, while longer pulses change the vortex chirality.

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M. Jaafar, R. Yanes, D. Perez de Lara, O. Chubykalo-Fesenko, A. Asenjo, E. M. Gonzalez, J. V. Anguita, M. Vazquez, J. L. Vicent. 2010-01-15. Control of the chirality and polarity of magnetic vortices in triangular nanodots. https://doi.org/10.1103/physrevb.81.054439

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