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arXiv · 2409.16129

The Arrhenius Law Prefactor in Permalloy Mesoscale Systems

James Delles·E. Dan Dahlberg
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Abstract

The Arrhenius equation was used to describe the dynamics of two-state switching in mesoscale, ferromagnetic particles. Using square, permalloy dots as an idealized two-state switching system, measurements of the prefactor of the Arrhenius law changed by 26 decades over barrier heights from 30 meV to 700 meV. Measurements of the prefactor ratios for a two well system revealed significant deviations from the common interpretation of the Arrhenius law. The anomalous Arrhenius prefactors and the prefactor ratios can be fitted to a modified model that includes entropic contributions to two-state transitions. Similar considerations are likely for the application of the Arrhenius law to other mesoscale systems.

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James Delles, E. Dan Dahlberg. 2024-09-24. The Arrhenius Law Prefactor in Permalloy Mesoscale Systems. https://arxiv.org/abs/2409.16129

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