Tunnel magnetoresistance of granular superparamagnetic and ferrimagnetic structures
Autor(a) principal: | |
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Data de Publicação: | 2022 |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | https://doi.org/10.34624/nmse.v4i1.29956 |
Resumo: | Applicable magnetic sensors based on nanogranular ferromagnetic materials were developed already more than 25 years ago. Since the then, nanotechnology has advanced significantly. New methods for manufacturing agglomerated core-shell structures have emerged. This opens up new possibilities of sensor fabrication and an opportunity for reassessment of the electric and magnetic properties of ideal granular structures. This work represents a comprehensive study of the intergranular resistivity, tunnel magnetoresistance and magnetic field sensibility of superparamagnetic and ferro(ferri)magnetic granular materials. Starting with the tunnel resistance of a granular metal network in which the grains are interconnected by insulating barriers, the tunnel magnetoresistance is calculated under consideration of the temperatures dependencies of magnetization, spin polarization and the magnetic flux dependencies of magnetization and tunnelling barrier height. Granular, superparamagnetic materials show a higher magnetic field sensitivity than ferromagnetic ones. They show a lower temperature coefficient of the tunnel magnetoresistance. Owing to their small magnetic response a higher temperature, superparamagnetic ferrimagnetic oxides are not suitable for application at room temperature. Ferromagnetic nanoparticles possess a high field sensitivity only in a small region of 0.1 to 0.5 T. |
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Tunnel magnetoresistance of granular superparamagnetic and ferrimagnetic structuresApplicable magnetic sensors based on nanogranular ferromagnetic materials were developed already more than 25 years ago. Since the then, nanotechnology has advanced significantly. New methods for manufacturing agglomerated core-shell structures have emerged. This opens up new possibilities of sensor fabrication and an opportunity for reassessment of the electric and magnetic properties of ideal granular structures. This work represents a comprehensive study of the intergranular resistivity, tunnel magnetoresistance and magnetic field sensibility of superparamagnetic and ferro(ferri)magnetic granular materials. Starting with the tunnel resistance of a granular metal network in which the grains are interconnected by insulating barriers, the tunnel magnetoresistance is calculated under consideration of the temperatures dependencies of magnetization, spin polarization and the magnetic flux dependencies of magnetization and tunnelling barrier height. Granular, superparamagnetic materials show a higher magnetic field sensitivity than ferromagnetic ones. They show a lower temperature coefficient of the tunnel magnetoresistance. Owing to their small magnetic response a higher temperature, superparamagnetic ferrimagnetic oxides are not suitable for application at room temperature. Ferromagnetic nanoparticles possess a high field sensitivity only in a small region of 0.1 to 0.5 T.UA Editora2022-12-08info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articleapplication/pdfhttps://doi.org/10.34624/nmse.v4i1.29956https://doi.org/10.34624/nmse.v4i1.29956Nanomaterials Science & Engineering; Vol 4 No 1 (2022): Nanomaterials Science & Engineering; 10-20Journal of Nanomaterials Science and Nanotechnology; Vol. 4 Núm. 1 (2022): Nanomaterials Science & Engineering; 10-20Journal of Nanomaterials Science and Nanotechnology; Vol. 4 No 1 (2022): Nanomaterials Science & Engineering; 10-20Nanomaterials Science & Engineering; vol. 4 n.º 1 (2022): Nanomaterials Science & Engineering; 10-202184-70022184-7002reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAPenghttps://proa.ua.pt/index.php/nmse/article/view/29956https://proa.ua.pt/index.php/nmse/article/view/29956/21162Copyright (c) 2022 Nanomaterials Science & Engineeringhttp://creativecommons.org/licenses/by-nc/4.0info:eu-repo/semantics/openAccessSuchaneck, Gunnar2022-12-27T02:15:28Zoai:proa.ua.pt:article/29956Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T16:28:53.799686Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Tunnel magnetoresistance of granular superparamagnetic and ferrimagnetic structures |
title |
Tunnel magnetoresistance of granular superparamagnetic and ferrimagnetic structures |
spellingShingle |
Tunnel magnetoresistance of granular superparamagnetic and ferrimagnetic structures Suchaneck, Gunnar |
title_short |
Tunnel magnetoresistance of granular superparamagnetic and ferrimagnetic structures |
title_full |
Tunnel magnetoresistance of granular superparamagnetic and ferrimagnetic structures |
title_fullStr |
Tunnel magnetoresistance of granular superparamagnetic and ferrimagnetic structures |
title_full_unstemmed |
Tunnel magnetoresistance of granular superparamagnetic and ferrimagnetic structures |
title_sort |
Tunnel magnetoresistance of granular superparamagnetic and ferrimagnetic structures |
author |
Suchaneck, Gunnar |
author_facet |
Suchaneck, Gunnar |
author_role |
author |
dc.contributor.author.fl_str_mv |
Suchaneck, Gunnar |
description |
Applicable magnetic sensors based on nanogranular ferromagnetic materials were developed already more than 25 years ago. Since the then, nanotechnology has advanced significantly. New methods for manufacturing agglomerated core-shell structures have emerged. This opens up new possibilities of sensor fabrication and an opportunity for reassessment of the electric and magnetic properties of ideal granular structures. This work represents a comprehensive study of the intergranular resistivity, tunnel magnetoresistance and magnetic field sensibility of superparamagnetic and ferro(ferri)magnetic granular materials. Starting with the tunnel resistance of a granular metal network in which the grains are interconnected by insulating barriers, the tunnel magnetoresistance is calculated under consideration of the temperatures dependencies of magnetization, spin polarization and the magnetic flux dependencies of magnetization and tunnelling barrier height. Granular, superparamagnetic materials show a higher magnetic field sensitivity than ferromagnetic ones. They show a lower temperature coefficient of the tunnel magnetoresistance. Owing to their small magnetic response a higher temperature, superparamagnetic ferrimagnetic oxides are not suitable for application at room temperature. Ferromagnetic nanoparticles possess a high field sensitivity only in a small region of 0.1 to 0.5 T. |
publishDate |
2022 |
dc.date.none.fl_str_mv |
2022-12-08 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
https://doi.org/10.34624/nmse.v4i1.29956 https://doi.org/10.34624/nmse.v4i1.29956 |
url |
https://doi.org/10.34624/nmse.v4i1.29956 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
https://proa.ua.pt/index.php/nmse/article/view/29956 https://proa.ua.pt/index.php/nmse/article/view/29956/21162 |
dc.rights.driver.fl_str_mv |
Copyright (c) 2022 Nanomaterials Science & Engineering http://creativecommons.org/licenses/by-nc/4.0 info:eu-repo/semantics/openAccess |
rights_invalid_str_mv |
Copyright (c) 2022 Nanomaterials Science & Engineering http://creativecommons.org/licenses/by-nc/4.0 |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf |
dc.publisher.none.fl_str_mv |
UA Editora |
publisher.none.fl_str_mv |
UA Editora |
dc.source.none.fl_str_mv |
Nanomaterials Science & Engineering; Vol 4 No 1 (2022): Nanomaterials Science & Engineering; 10-20 Journal of Nanomaterials Science and Nanotechnology; Vol. 4 Núm. 1 (2022): Nanomaterials Science & Engineering; 10-20 Journal of Nanomaterials Science and Nanotechnology; Vol. 4 No 1 (2022): Nanomaterials Science & Engineering; 10-20 Nanomaterials Science & Engineering; vol. 4 n.º 1 (2022): Nanomaterials Science & Engineering; 10-20 2184-7002 2184-7002 reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
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Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
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RCAAP |
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RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
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Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
repository.mail.fl_str_mv |
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1799130746637516800 |