Generation of highly anisotropic physical properties in ferromagnetic thin films controlled by their differently oriented nano-sheets
We fabricated ferromagnetic nano-crystalline thin films of Co, Fe, Co–Fe and Co-rich and Fe-rich, Co–MT and Fe–MT (MT = transition metal), constituted by nano-sheets with a controlled slant. Visualization of these nano-sheets by Scanning Tunneling Microscopy and High-Resolution Transmission Electron...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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AIP Publishing LLC
2024-02-01
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| Series: | AIP Advances |
| Online Access: | http://dx.doi.org/10.1063/9.0000813 |
| _version_ | 1797278300633038848 |
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| author | C. Favieres J. Vergara C. Magén M. R. Ibarra V. Madurga |
| author_facet | C. Favieres J. Vergara C. Magén M. R. Ibarra V. Madurga |
| author_sort | C. Favieres |
| collection | DOAJ |
| description | We fabricated ferromagnetic nano-crystalline thin films of Co, Fe, Co–Fe and Co-rich and Fe-rich, Co–MT and Fe–MT (MT = transition metal), constituted by nano-sheets with a controlled slant. Visualization of these nano-sheets by Scanning Tunneling Microscopy and High-Resolution Transmission Electron Microscopy (HRTEM) showed typically tilt angles ≈56° with respect to the substrate plane, and nano-sheets ≈3.0–4.0 nm thick, ≈30–100 nm wide, and ≈200–300 nm long, with an inter-sheet distance of ≈0.9–1.2 nm, depending on their constitutive elements. Induced by this nano-morphology, these films exhibited large uniaxial magnetic anisotropy in the plane, the easy direction of magnetization being parallel to the longitudinal direction of the nano-sheets. In the as-grown films, typical values of the anisotropy field were between Hk ≈ 48 and 110 kA/m depending on composition. The changes in the nano-morphology caused by thermal treatments, and hence in the anisotropic properties, were also visualized by HRTEM, including chemical analysis at the nano-scale. Some films retained their nano-sheet morphology and increased their anisotropies by up to three times after being heated to at least 500 °C: for example, the thermal treatments produced crystallization processes and the growth of CoV and CoFe magnetic phases, maintaining the nano-sheet morphology. In contrast, other annealed films, Co, Fe, CoZn, CoCu… lost their nano-sheet morphology and hence their anisotropies. This work opens a path of study for these new magnetically anisotropic materials, particularly with respect to the nano-morphological and structural changes related to the increase in magnetic anisotropy. |
| first_indexed | 2024-03-07T16:00:17Z |
| format | Article |
| id | doaj.art-aee5a2e616244b2fb11ba9a0c60b2b18 |
| institution | Directory Open Access Journal |
| issn | 2158-3226 |
| language | English |
| last_indexed | 2024-03-07T16:00:17Z |
| publishDate | 2024-02-01 |
| publisher | AIP Publishing LLC |
| record_format | Article |
| series | AIP Advances |
| spelling | doaj.art-aee5a2e616244b2fb11ba9a0c60b2b182024-03-04T21:29:33ZengAIP Publishing LLCAIP Advances2158-32262024-02-01142025237025237-810.1063/9.0000813Generation of highly anisotropic physical properties in ferromagnetic thin films controlled by their differently oriented nano-sheetsC. Favieres0J. Vergara1C. Magén2M. R. Ibarra3V. Madurga4Laboratorio de Magnetismo, Departamento de Ciencias, Física, Universidad Pública de Navarra (UPNA), Campus de Arrosadía, Pamplona, EspañaLaboratorio de Magnetismo, Departamento de Ciencias, Física, Universidad Pública de Navarra (UPNA), Campus de Arrosadía, Pamplona, EspañaInstituto de Nanociencia y de Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, Zaragoza, EspañaInstituto de Nanociencia y de Materiales de Aragón (INMA), CSIC-Universidad de Zaragoza, Zaragoza, EspañaLaboratorio de Magnetismo, Departamento de Ciencias, Física, Universidad Pública de Navarra (UPNA), Campus de Arrosadía, Pamplona, EspañaWe fabricated ferromagnetic nano-crystalline thin films of Co, Fe, Co–Fe and Co-rich and Fe-rich, Co–MT and Fe–MT (MT = transition metal), constituted by nano-sheets with a controlled slant. Visualization of these nano-sheets by Scanning Tunneling Microscopy and High-Resolution Transmission Electron Microscopy (HRTEM) showed typically tilt angles ≈56° with respect to the substrate plane, and nano-sheets ≈3.0–4.0 nm thick, ≈30–100 nm wide, and ≈200–300 nm long, with an inter-sheet distance of ≈0.9–1.2 nm, depending on their constitutive elements. Induced by this nano-morphology, these films exhibited large uniaxial magnetic anisotropy in the plane, the easy direction of magnetization being parallel to the longitudinal direction of the nano-sheets. In the as-grown films, typical values of the anisotropy field were between Hk ≈ 48 and 110 kA/m depending on composition. The changes in the nano-morphology caused by thermal treatments, and hence in the anisotropic properties, were also visualized by HRTEM, including chemical analysis at the nano-scale. Some films retained their nano-sheet morphology and increased their anisotropies by up to three times after being heated to at least 500 °C: for example, the thermal treatments produced crystallization processes and the growth of CoV and CoFe magnetic phases, maintaining the nano-sheet morphology. In contrast, other annealed films, Co, Fe, CoZn, CoCu… lost their nano-sheet morphology and hence their anisotropies. This work opens a path of study for these new magnetically anisotropic materials, particularly with respect to the nano-morphological and structural changes related to the increase in magnetic anisotropy.http://dx.doi.org/10.1063/9.0000813 |
| spellingShingle | C. Favieres J. Vergara C. Magén M. R. Ibarra V. Madurga Generation of highly anisotropic physical properties in ferromagnetic thin films controlled by their differently oriented nano-sheets AIP Advances |
| title | Generation of highly anisotropic physical properties in ferromagnetic thin films controlled by their differently oriented nano-sheets |
| title_full | Generation of highly anisotropic physical properties in ferromagnetic thin films controlled by their differently oriented nano-sheets |
| title_fullStr | Generation of highly anisotropic physical properties in ferromagnetic thin films controlled by their differently oriented nano-sheets |
| title_full_unstemmed | Generation of highly anisotropic physical properties in ferromagnetic thin films controlled by their differently oriented nano-sheets |
| title_short | Generation of highly anisotropic physical properties in ferromagnetic thin films controlled by their differently oriented nano-sheets |
| title_sort | generation of highly anisotropic physical properties in ferromagnetic thin films controlled by their differently oriented nano sheets |
| url | http://dx.doi.org/10.1063/9.0000813 |
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