Interfacial coupling effect of Cr_2O_3 on the magnetic properties of Fe_72Ga_28 thin films

Here it is investigated the effect of the antiferromagnet Cr_2O_3 on the magnetic properties of ferromagnetic Fe_72Ga_28 thin films. Sputtered Fe_72Ga_28 layers have their magnetization in the sample plane with a magnetic fluctuation that gives rise to magnetic ripple. In order to turn its magnetiza...

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Detalles Bibliográficos
Autores: Hontecillas, I., Maicas, M., Andrés, J.P., Ranchal Sánchez, Rocío
Tipo de recurso: artículo
Fecha de publicación:2021
País:España
Institución:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/8418
Acceso en línea:https://hdl.handle.net/20.500.14352/8418
Access Level:acceso abierto
Palabra clave:538.9
Random-field model
Exchange bias
Fe-Ga
Anisotropy
Surface
Física de materiales
Física del estado sólido
2211 Física del Estado Sólido
Descripción
Sumario:Here it is investigated the effect of the antiferromagnet Cr_2O_3 on the magnetic properties of ferromagnetic Fe_72Ga_28 thin films. Sputtered Fe_72Ga_28 layers have their magnetization in the sample plane with a magnetic fluctuation that gives rise to magnetic ripple. In order to turn its magnetization into the out of plane (OOP) direction, it has been magnetically coupled with Cr_2O_3 that has magnetic moments along the c-axis, that is the perpendicular direction when properly aligned. Cr2O3 has been obtained from Cr oxidation, whereas Fe_72Ga_28 has been deposited on top of it by sputtering in the ballistic regime. Although a uniaxial in-plane magnetic anisotropy is expected for Fe_72Ga_28 thickness above 100 nm, the interfacial coupling with Cr2O3 prevents this anisotropy. The formation of stripe domains in Fe_72Ga_28 above a critical thickness reveals the enhancement of the out of plane component of the Fe_72Ga_28 magnetization with respect to uncoupled layers. Due to the interface coupling, the Fe72Ga28 magnetization turns into the out-of-plane direction as its thickness is gradually reduced, and a perpendicular magnetic anisotropy of 3.10^6 erg.cm^(-3) is inferred from experimental results. Eventually, the coupling between Cr_2O_3 and Fe_72Ga_28 promotes an exchange-bias effect that has been well fitted by means of the random field model.