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arXiv · 1401.7749

Quantitative Decoding of Interactions in Tunable Nanomagnet Arrays Using First Order Reversal Curves

Dustin A. Gilbert·Gergely T. Zimanyi·Randy K. Dumas·Michael Winklhofer·Alicia Gomez·Nasim Eibagi·J. L. Vicent·Kai Liu
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Abstract

To develop a full understanding of interactions in nanomagnet arrays is a persistent challenge, critically impacting their technological acceptance. This paper reports the experimental, numerical and analytical investigation of interactions in arrays of Co nanoellipses using the first-order reversal curve (FORC) technique. A mean-field analysis has revealed the physical mechanisms giving rise to all of the observed features: a shift of the non-interacting FORC-ridge at the low-H$_c$ end off the local coercivity H$_c$ axis; a stretch of the FORC-ridge at the high-H$_c$ end without shifting it off the H$_c$ axis; and a formation of a tilted edge connected to the ridge at the low-H$_c$ end. Changing from flat to Gaussian coercivity distribution produces a negative feature, bends the ridge, and broadens the edge. Finally, nearest neighbor interactions segment the FORC-ridge. These results demonstrate that the FORC approach provides a comprehensive framework to qualitatively and quantitatively decode interactions in nanomagnet arrays.

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Dustin A. Gilbert, Gergely T. Zimanyi, Randy K. Dumas, Michael Winklhofer, Alicia Gomez, Nasim Eibagi, J. L. Vicent, Kai Liu. 2014-01-30. Quantitative Decoding of Interactions in Tunable Nanomagnet Arrays Using First Order Reversal Curves. https://doi.org/10.1038/srep04204

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