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arXiv · 2201.09011

Magnetization Reversal Across Multiple Serial Barriers in a Single Fe$_3$O$_4$ Nanoparticle

Sagar Paul·Ganesh Kotagiri·Rini Ganguly·Annapoorni Subramanian·Hervé Courtois·Clemens B. Winkelmann·Anjan K. Gupta
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Abstract

Depinning of nanoscale magnetic textures, such as domain walls, vortices and skyrmions, is of paramount importance for magnetic storage and information processing. We measure time-resolved magnetic switching statistics of an individual, non-single-domain Fe$_3$O$_4$ nanoparticle using a micrometer-scale superconducting quantum interference device. Surprisingly, a strong narrowing of the waiting-time distributions before reaching the final state is observed as compared to the exponential distribution expected for a single barrier. The magnetization reversal across the nanostructure is thus shown to result from multiple serial barriers in the minimum energy pathway.

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Sagar Paul, Ganesh Kotagiri, Rini Ganguly, Annapoorni Subramanian, Hervé Courtois, Clemens B. Winkelmann, Anjan K. Gupta. 2022-01-22. Magnetization Reversal Across Multiple Serial Barriers in a Single Fe$_3$O$_4$ Nanoparticle. https://doi.org/10.1103/physrevb.105.l180410

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