Phase Diagram of Magnetization Reversal Processes in Nanorings

Wen Zhang; Stephan Haas

doi:10.1103/physrevb.81.064433

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arXiv · 0912.0319

Phase Diagram of Magnetization Reversal Processes in Nanorings

Wen Zhang·Stephan Haas

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Abstract

We investigate magnetization reversal processes of magnetic nanorings. Using a recently developed efficient cartesian coordinates fast multipole method, magnetization switching phase diagrams are constructed for such structures. We find that the dominant switching mechanisms strongly depend on the relative spatial dimensions of the rings, i.e. height, width and radius. Furthermore, they are found to depend on a characteristic exchange length scale, which is determined by the competing short-range ferromagnetic and long-range dipolar interactions in these systems. Detailed simulations allow us to identify three novel switching mechanisms, which should be useful for building high density storage systems.

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Wen Zhang, Stephan Haas. 2009-12-02. Phase Diagram of Magnetization Reversal Processes in Nanorings. https://doi.org/10.1103/physrevb.81.064433

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