Benito, L, Clark, L orcid.org/0000-0001-8245-162X, Almeida, TP orcid.org/0000-0003-4683-6279 et al. (4 more authors) (2020) Sputter-engineering a first-order magnetic phase transition in sub-15-nm-thick single-crystal FeRh films. Physical Review Materials, 4 (12). 123402. ISSN 2475-9953
Abstract
Equiatomic FeRh alloys undergo a fascinating first-order metamagnetic phase transition (FOMPT) just above room temperature, which has attracted reinvigorated interest for applications in spintronics. Until now, all attempts to grow nanothin FeRh alloy films have consistently shown that FeRh layers tend to grow in the Volmer-Weber growth mode. Here we show that sputter-grown sub-15-nm-thick FeRh alloy films deposited at low sputter-gas pressure, typically ∼0.1 Pa, onto (001)-oriented MgO substrates, grow in a peening-induced Frank-van der Merwe growth mode for FeRh film thicknesses above 5 nm, circumventing this major drawback. The bombardment of high-energy sputtered atoms, the atom-peening effect, induces a rebalancing between adsorbate-surface and adsorbate-adsorbate interactions, leading to the formation of a smooth continuous nanothin FeRh film. Chemical order in the films increases with the FeRh thickness, tFeRh, and varies monotonically from 0.75 up to 0.9. Specular x-ray diffraction scans around Bragg peaks show Pendellösung fringes for films with tFeRh≥5.2 nm, which reflects in smooth well-ordered densified single-crystal FeRh layers. The nanothin film's roughness varies from 0.6 down to about 0.1 nm as tFeRh increases, and scales linearly with the integral breadth of the rocking curve, proving its microstructured origin. Magnetometry shows that the FOMPT in the nanothin films is qualitatively similar to that of the bulk alloy, except for the thinnest film of 3.7 nm.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | ©2020 American Physical Society. This is an author produced version of an article published in Physical Review Materials. Uploaded in accordance with the publisher's self-archiving policy. |
Dates: |
|
Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Physics and Astronomy (Leeds) > Condensed Matter (Leeds) |
Funding Information: | Funder Grant number EU - European Union 748691 EPSRC (Engineering and Physical Sciences Research Council) EP/M018504/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 16 Oct 2020 10:34 |
Last Modified: | 08 Jan 2025 13:01 |
Status: | Published |
Publisher: | American Physical Society |
Identification Number: | 10.1103/PhysRevMaterials.4.123402 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:166687 |