Cargando…

Grain boundary anisotropy on nano-polycrystalline magnetic thin films

Grain boundaries in polycrystalline thin films with crystallite sizes at nanoscale presents regions characterized by a high degree of local structural disorder. As a consequence, great values of the associated local anisotropies are expected. On this regard, a systematic investigation of the effect...

Descripción completa

Detalles Bibliográficos
Autores principales: Agudelo-Giraldo, Jose D., Restrepo-Parra, Elisabeth, Restrepo, Johans
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Nature Publishing Group UK 2020
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7081355/
https://www.ncbi.nlm.nih.gov/pubmed/32193511
http://dx.doi.org/10.1038/s41598-020-61979-z
_version_ 1783508162072018944
author Agudelo-Giraldo, Jose D.
Restrepo-Parra, Elisabeth
Restrepo, Johans
author_facet Agudelo-Giraldo, Jose D.
Restrepo-Parra, Elisabeth
Restrepo, Johans
author_sort Agudelo-Giraldo, Jose D.
collection PubMed
description Grain boundaries in polycrystalline thin films with crystallite sizes at nanoscale presents regions characterized by a high degree of local structural disorder. As a consequence, great values of the associated local anisotropies are expected. On this regard, a systematic investigation of the effect of the grain boundary anisotropy on the magnetic properties in such type of nanostructured systems is addressed. For developing this work, a standard Monte Carlo simulation in the framework of classical Heisenberg spins was carried out, with a Hamiltonian involving exchange couplings, dipolar interactions, Zeeman interaction and contributions of cubic magneto-crystalline anisotropy. A quantification of local structural disorder was considered. Results revealed that i) by keeping the same number of grains, different organizations give rise to different spontaneous magnetizations, ii) the critical exponent of the magnetization differs of pure models, which is attributed to the complexity of the lattice and consistent with a distribution of critical temperatures, iii) Boundary anisotropy varies with temperature and its strength are determinant factors for blocking temperatures, and iv) Boundary anisotropy inside in the hysteretic properties where coercive field variations are observed.
format Online
Article
Text
id pubmed-7081355
institution National Center for Biotechnology Information
language English
publishDate 2020
publisher Nature Publishing Group UK
record_format MEDLINE/PubMed
spelling pubmed-70813552020-03-23 Grain boundary anisotropy on nano-polycrystalline magnetic thin films Agudelo-Giraldo, Jose D. Restrepo-Parra, Elisabeth Restrepo, Johans Sci Rep Article Grain boundaries in polycrystalline thin films with crystallite sizes at nanoscale presents regions characterized by a high degree of local structural disorder. As a consequence, great values of the associated local anisotropies are expected. On this regard, a systematic investigation of the effect of the grain boundary anisotropy on the magnetic properties in such type of nanostructured systems is addressed. For developing this work, a standard Monte Carlo simulation in the framework of classical Heisenberg spins was carried out, with a Hamiltonian involving exchange couplings, dipolar interactions, Zeeman interaction and contributions of cubic magneto-crystalline anisotropy. A quantification of local structural disorder was considered. Results revealed that i) by keeping the same number of grains, different organizations give rise to different spontaneous magnetizations, ii) the critical exponent of the magnetization differs of pure models, which is attributed to the complexity of the lattice and consistent with a distribution of critical temperatures, iii) Boundary anisotropy varies with temperature and its strength are determinant factors for blocking temperatures, and iv) Boundary anisotropy inside in the hysteretic properties where coercive field variations are observed. Nature Publishing Group UK 2020-03-19 /pmc/articles/PMC7081355/ /pubmed/32193511 http://dx.doi.org/10.1038/s41598-020-61979-z Text en © The Author(s) 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
spellingShingle Article
Agudelo-Giraldo, Jose D.
Restrepo-Parra, Elisabeth
Restrepo, Johans
Grain boundary anisotropy on nano-polycrystalline magnetic thin films
title Grain boundary anisotropy on nano-polycrystalline magnetic thin films
title_full Grain boundary anisotropy on nano-polycrystalline magnetic thin films
title_fullStr Grain boundary anisotropy on nano-polycrystalline magnetic thin films
title_full_unstemmed Grain boundary anisotropy on nano-polycrystalline magnetic thin films
title_short Grain boundary anisotropy on nano-polycrystalline magnetic thin films
title_sort grain boundary anisotropy on nano-polycrystalline magnetic thin films
topic Article
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7081355/
https://www.ncbi.nlm.nih.gov/pubmed/32193511
http://dx.doi.org/10.1038/s41598-020-61979-z
work_keys_str_mv AT agudelogiraldojosed grainboundaryanisotropyonnanopolycrystallinemagneticthinfilms
AT restrepoparraelisabeth grainboundaryanisotropyonnanopolycrystallinemagneticthinfilms
AT restrepojohans grainboundaryanisotropyonnanopolycrystallinemagneticthinfilms