Effective demagnetizing tensors in arrays of magnetic nanopillars

A model describing the effect of magnetic dipolar interactions on the susceptibility of magnetic nanopillars is presented. It is an extension of a recently reported model for three-dimensional randomlike dispersions of nearly spherical nanoparticles in equilibrium [Sánchez et al., Phys. Rev. B 95, 1...

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Autores:
Mendoza Zelis, P
Vega, Víctor V
Prida, V M
Costa Arzuza, Luis Carlos
Beron, Fanny
Pirota, Kleber Roberto
Lopez Ruiz, Roman
Sanchez, Francisco Homero
Tipo de recurso:
Article of journal
Fecha de publicación:
2017
Institución:
Corporación Universidad de la Costa
Repositorio:
REDICUC - Repositorio CUC
Idioma:
OAI Identifier:
oai:repositorio.cuc.edu.co:11323/1161
Acceso en línea:
https://hdl.handle.net/11323/1161
https://repositorio.cuc.edu.co/
Palabra clave:
Magnetism
Nanoparticles
Nanopillars
Dipolar Interactions
Demagnetizing Factors
Rights
openAccess
License
Atribución – No comercial – Compartir igual
Description
Summary:A model describing the effect of magnetic dipolar interactions on the susceptibility of magnetic nanopillars is presented. It is an extension of a recently reported model for three-dimensional randomlike dispersions of nearly spherical nanoparticles in equilibrium [Sánchez et al., Phys. Rev. B 95, 134421 (2017)], to well-ordered arrays of nanoparticles out of equilibrium. To test it, a high-quality benchmark consisting of a two-dimensional hexagonal arrangement of quasi-identical parallel nickel nanopillars embedded in a porous alumina template was fabricated. This model is based on an effective demagnetizing tensor, which only depends on a few morphological parameters of the sample, as the nearest-neighbor distance between pillars and the volume fraction of pillars in the specimen. It allows us to obtain the nanopillar intrinsic susceptibility tensor from the magnetic response of the nanopillar ensemble. The values of the in-plane and normal-to-plane susceptibility of the sample are successfully predicted by the model. Furthermore, the model reproduces the susceptibility in the applied field direction, measured for different applied field angles. In this way, it provides a simple and accurate treatment to account for the complex magnetic effects produced by dipolar interactions.