Magnetostatic interaction between Bloch Point nanospheres

Cristobal Zambrano-Rabanal; Boris Valderrama; Felipe Tejo; Ricardo Gabriel Elías; Alvaro S. Nunez; Vagson L. Carvalho-Santos; Nicolás Vidal-Silva

arXiv · 2211.09161

Magnetostatic interaction between Bloch Point nanospheres

Cristobal Zambrano-Rabanal·Boris Valderrama·Felipe Tejo·Ricardo Gabriel Elías·Alvaro S. Nunez·Vagson L. Carvalho-Santos·Nicolás Vidal-Silva

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Abstract

Three-dimensional topological textures have become a topic of intense interest in recent years. Through analytical calculations, this work determines the magnetostatic field produced by a Bloch Point (BP) singularity confined in a magnetic nanosphere. It is observed that BPs hosted in a nanosphere generate magnetic fields with quadrupolar nature. This finding is interesting because it shows the possibility of obtaining quadrupole magnetic fields with just one magnetic particle, unlike other propositions considering arrays of magnetic elements to generate this kind of field. The obtained magnetostatic field allows us to determine the interaction between two BPs as a function of the relative orientation of their polarities and the distance between them. It is shown that depending on the rotation of one BP related to the other, the magnetostatic interaction varies in strength and character, being attractive or repulsive. The obtained results reveal that the BP interaction has a complex behavior beyond topological charge-mediated interaction.

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BibTeX RIS

Cristobal Zambrano-Rabanal, Boris Valderrama, Felipe Tejo, Ricardo Gabriel Elías, Alvaro S. Nunez, Vagson L. Carvalho-Santos, Nicolás Vidal-Silva. 2022-11-16. Magnetostatic interaction between Bloch Point nanospheres. https://arxiv.org/abs/2211.09161

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