Origin of perpendicular magnetic anisotropy in amorphous thin films
Abstract The emergence of perpendicular magnetic anisotropy (PMA) in amorphous thin films, which eventually transforms the magnetic spins form an in-plane to the out-of-plane configuration, also known as a spin-reorientation transition (SRT), is a fundamental roadblock to attain the high flux concen...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2021-02-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-020-78950-7 |
| _version_ | 1818842741084258304 |
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| author | Daniel Lordan Guannan Wei Paul McCloskey Cian O’Mathuna Ansar Masood |
| author_facet | Daniel Lordan Guannan Wei Paul McCloskey Cian O’Mathuna Ansar Masood |
| author_sort | Daniel Lordan |
| collection | DOAJ |
| description | Abstract The emergence of perpendicular magnetic anisotropy (PMA) in amorphous thin films, which eventually transforms the magnetic spins form an in-plane to the out-of-plane configuration, also known as a spin-reorientation transition (SRT), is a fundamental roadblock to attain the high flux concentration advantage of these functional materials for broadband applications. The present work is focused on unfolding the origin of PMA in amorphous thin films deposited by magnetron sputtering. The amorphous films were deposited under a broad range of sputtering pressure (1.6–6.2 mTorr), and its effect on the thin film growth mechanisms was correlated to the static global magnetic behaviours, magnetic domain structure, and dynamic magnetic performance. The films deposited under low-pressure revealed a dominant in-plane uniaxial anisotropy along with an emerging, however feeble, perpendicular component, which eventually evolved as a dominant PMA when deposited under high-pressure sputtering. This change in the nature of anisotropy redefined the orientation of spins from in-plane to out-of-plane. The SRT in amorphous films was attributed to the dramatic change in the growth mechanism of disorder atomic structure from a homogeneously dispersed to a porous columnar microstructure. We suggest the origin of PMA is associated with the columnar growth of the amorphous films, which can be eluded by a careful selection of a deposition pressure regime to avoid its detrimental effect on the soft magnetic performance. To the author’s best knowledge, no such report links the sputtering pressure as a governing mechanism of perpendicular magnetisation in technologically important amorphous thin films. |
| first_indexed | 2024-12-19T04:46:47Z |
| format | Article |
| id | doaj.art-5d8c7a684d40411b8f23f4d88d09c371 |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-12-19T04:46:47Z |
| publishDate | 2021-02-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-5d8c7a684d40411b8f23f4d88d09c3712022-12-21T20:35:27ZengNature PortfolioScientific Reports2045-23222021-02-0111111210.1038/s41598-020-78950-7Origin of perpendicular magnetic anisotropy in amorphous thin filmsDaniel Lordan0Guannan Wei1Paul McCloskey2Cian O’Mathuna3Ansar Masood4Micro & Nano Systems Centre, Tyndall National Institute, University College CorkMicro & Nano Systems Centre, Tyndall National Institute, University College CorkMicro & Nano Systems Centre, Tyndall National Institute, University College CorkMicro & Nano Systems Centre, Tyndall National Institute, University College CorkMicro & Nano Systems Centre, Tyndall National Institute, University College CorkAbstract The emergence of perpendicular magnetic anisotropy (PMA) in amorphous thin films, which eventually transforms the magnetic spins form an in-plane to the out-of-plane configuration, also known as a spin-reorientation transition (SRT), is a fundamental roadblock to attain the high flux concentration advantage of these functional materials for broadband applications. The present work is focused on unfolding the origin of PMA in amorphous thin films deposited by magnetron sputtering. The amorphous films were deposited under a broad range of sputtering pressure (1.6–6.2 mTorr), and its effect on the thin film growth mechanisms was correlated to the static global magnetic behaviours, magnetic domain structure, and dynamic magnetic performance. The films deposited under low-pressure revealed a dominant in-plane uniaxial anisotropy along with an emerging, however feeble, perpendicular component, which eventually evolved as a dominant PMA when deposited under high-pressure sputtering. This change in the nature of anisotropy redefined the orientation of spins from in-plane to out-of-plane. The SRT in amorphous films was attributed to the dramatic change in the growth mechanism of disorder atomic structure from a homogeneously dispersed to a porous columnar microstructure. We suggest the origin of PMA is associated with the columnar growth of the amorphous films, which can be eluded by a careful selection of a deposition pressure regime to avoid its detrimental effect on the soft magnetic performance. To the author’s best knowledge, no such report links the sputtering pressure as a governing mechanism of perpendicular magnetisation in technologically important amorphous thin films.https://doi.org/10.1038/s41598-020-78950-7 |
| spellingShingle | Daniel Lordan Guannan Wei Paul McCloskey Cian O’Mathuna Ansar Masood Origin of perpendicular magnetic anisotropy in amorphous thin films Scientific Reports |
| title | Origin of perpendicular magnetic anisotropy in amorphous thin films |
| title_full | Origin of perpendicular magnetic anisotropy in amorphous thin films |
| title_fullStr | Origin of perpendicular magnetic anisotropy in amorphous thin films |
| title_full_unstemmed | Origin of perpendicular magnetic anisotropy in amorphous thin films |
| title_short | Origin of perpendicular magnetic anisotropy in amorphous thin films |
| title_sort | origin of perpendicular magnetic anisotropy in amorphous thin films |
| url | https://doi.org/10.1038/s41598-020-78950-7 |
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