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arXiv · 1108.3521

Magneto-optical imaging of voltage-controlled magnetization reorientation

A. Brandlmaier·M. Brasse·S. Geprägs·M. Weiler·R. Gross·S. T. B. Goennenwein
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Abstract

We study the validity and limitations of a macrospin model to describe the voltage-controlled manipulation of ferromagnetic magnetization in nickel thin film/piezoelectric actuator hybrid structures. To this end, we correlate simultaneously measured spatially resolved magneto-optical Kerr effect imaging and integral magnetotransport measurements at room temperature. Our results show that a macrospin approach is adequate to model the magnetoresistance as a function of the voltage applied to the hybrid, except for a narrow region around the coercive field - where the magnetization reorientation evolves via domain effects. Thus, on length scales much larger than the typical magnetic domain size, the voltage control of magnetization is well reproduced by a simple Stoner-Wohlfarth type macrospin model.

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A. Brandlmaier, M. Brasse, S. Geprägs, M. Weiler, R. Gross, S. T. B. Goennenwein. 2011-08-17. Magneto-optical imaging of voltage-controlled magnetization reorientation. https://doi.org/10.1140/epjb/e2012-20675-4

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