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arXiv · 1008.4963

Chirality control via double vortices in asymmetric Co dots

Randy K. Dumas·Dustin A. Gilbert·Nasim Eibagi·Kai Liu
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Abstract

Reproducible control of the magnetic vortex state in nanomagnets is of critical importance. We report on chirality control by manipulating the size and/or thickness of asymmetric Co dots. Below a critical diameter and/or thickness, chirality control is achieved by the nucleation of single vortex. Interestingly, above these critical dimensions chirality control is realized by the nucleation and subsequent coalescence of two vortices, resulting in a single vortex with the opposite chirality as found in smaller dots. Micromagnetic simulations and magnetic force microscopy highlight the role of edge-bound halfvortices in facilitating the coalescence process.

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Randy K. Dumas, Dustin A. Gilbert, Nasim Eibagi, Kai Liu. 2011-03-02. Chirality control via double vortices in asymmetric Co dots. https://doi.org/10.1103/physrevb.83.060415

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