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Discontinuity in the Electronic Structure and Magnetic Order of β-Co(1+x)Ga(1−x)
The present work reports on the calculated electronic and magnetic structure of the binary Co-Ga system at high Co content. [Formula: see text]-CoGa adopts a simple cubic CsCl type structure. Well-ordered CoGa does not exhibit collective magnetism but is a paramagnetic, metallic compound. Neither Co...
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Formato: | Online Artículo Texto |
Lenguaje: | English |
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MDPI
2022
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Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9413009/ https://www.ncbi.nlm.nih.gov/pubmed/36013659 http://dx.doi.org/10.3390/ma15165523 |
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author | Fecher, Gerhard H. |
author_facet | Fecher, Gerhard H. |
author_sort | Fecher, Gerhard H. |
collection | PubMed |
description | The present work reports on the calculated electronic and magnetic structure of the binary Co-Ga system at high Co content. [Formula: see text]-CoGa adopts a simple cubic CsCl type structure. Well-ordered CoGa does not exhibit collective magnetism but is a paramagnetic, metallic compound. Neither Co nor Ga deficiency induces magnetic order; however, ferromagnetism is observed for Co-Ga anti-site disorder. The magnetic moment per cell increases by up to approximately 1.2 [Formula: see text] in the completely disordered body-centered cubic structure. With increasing Co content, Co [Formula: see text] Ga [Formula: see text] maintains the CsCl type structure and becomes ferromagnetic. Most importantly, a discontinuity of the magnetic order with composition is observed at about 10% excess Co, where a change from a low magnetic moment state to a high moment state is observed. This is accompanied by a change in the electronic structure and transport properties. The discontinuity is forced by the increasing exchange splitting related to the localized moment of the additional Co atoms that replace Ga. Subsequently, the magnetic moment increases continuously up to 2.5 [Formula: see text] for [Formula: see text]. For [Formula: see text] , the structure changes to a face-centered cubic structure with random site occupation and the magnetic moment further increases. Above the magnetic discontinuity, the Curie temperature increases linearly with the Co content from the onset of ferromagnetism, until it reaches its maximum in pure Co. |
format | Online Article Text |
id | pubmed-9413009 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2022 |
publisher | MDPI |
record_format | MEDLINE/PubMed |
spelling | pubmed-94130092022-08-27 Discontinuity in the Electronic Structure and Magnetic Order of β-Co(1+x)Ga(1−x) Fecher, Gerhard H. Materials (Basel) Article The present work reports on the calculated electronic and magnetic structure of the binary Co-Ga system at high Co content. [Formula: see text]-CoGa adopts a simple cubic CsCl type structure. Well-ordered CoGa does not exhibit collective magnetism but is a paramagnetic, metallic compound. Neither Co nor Ga deficiency induces magnetic order; however, ferromagnetism is observed for Co-Ga anti-site disorder. The magnetic moment per cell increases by up to approximately 1.2 [Formula: see text] in the completely disordered body-centered cubic structure. With increasing Co content, Co [Formula: see text] Ga [Formula: see text] maintains the CsCl type structure and becomes ferromagnetic. Most importantly, a discontinuity of the magnetic order with composition is observed at about 10% excess Co, where a change from a low magnetic moment state to a high moment state is observed. This is accompanied by a change in the electronic structure and transport properties. The discontinuity is forced by the increasing exchange splitting related to the localized moment of the additional Co atoms that replace Ga. Subsequently, the magnetic moment increases continuously up to 2.5 [Formula: see text] for [Formula: see text]. For [Formula: see text] , the structure changes to a face-centered cubic structure with random site occupation and the magnetic moment further increases. Above the magnetic discontinuity, the Curie temperature increases linearly with the Co content from the onset of ferromagnetism, until it reaches its maximum in pure Co. MDPI 2022-08-11 /pmc/articles/PMC9413009/ /pubmed/36013659 http://dx.doi.org/10.3390/ma15165523 Text en © 2022 by the author. https://creativecommons.org/licenses/by/4.0/Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). |
spellingShingle | Article Fecher, Gerhard H. Discontinuity in the Electronic Structure and Magnetic Order of β-Co(1+x)Ga(1−x) |
title | Discontinuity in the Electronic Structure and Magnetic Order of β-Co(1+x)Ga(1−x) |
title_full | Discontinuity in the Electronic Structure and Magnetic Order of β-Co(1+x)Ga(1−x) |
title_fullStr | Discontinuity in the Electronic Structure and Magnetic Order of β-Co(1+x)Ga(1−x) |
title_full_unstemmed | Discontinuity in the Electronic Structure and Magnetic Order of β-Co(1+x)Ga(1−x) |
title_short | Discontinuity in the Electronic Structure and Magnetic Order of β-Co(1+x)Ga(1−x) |
title_sort | discontinuity in the electronic structure and magnetic order of β-co(1+x)ga(1−x) |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9413009/ https://www.ncbi.nlm.nih.gov/pubmed/36013659 http://dx.doi.org/10.3390/ma15165523 |
work_keys_str_mv | AT fechergerhardh discontinuityintheelectronicstructureandmagneticorderofbco1xga1x |