Tuning the interfacial charge, orbital, and spin polarization properties in La0.67Sr0.33MnO3/La1-xSrxMnO3 bilayers

Carreira, S.J. ; Aguirre, M.H. (Universidad de Zaragoza) ; Briatico, J. ; Weschke, E. ; Steren, L.B.

Resumen: The possibility of controlling the interfacial properties of artificial oxide heterostructures is still attracting researchers in the field of materials engineering. Here, we used surface sensitive techniques and high-resolution transmission electron microscopy to investigate the evolution of the surface spin-polarization and lattice strains across the interfaces between La0.66Sr0.33MnO3 thin films and low-doped manganites as capping layers. We have been able to fine tune the interfacial spin-polarization by changing the capping layer thickness and composition. The spin-polarization was found to be the highest at a critical capping thickness that depends on the Sr doping. We explain the non-trivial magnetic profile by the combined effect of two mechanisms: On the one hand, the extra carriers supplied by the low-doped manganites that tend to compensate the overdoped interface, favouring locally a ferromagnetic double-exchange coupling. On the other hand, the evolution from a tensile-strained structure of the inner layers to a compressed structure at the surface that changes gradually the orbital occupation and hybridization of the 3d-Mn orbitals, being detrimental for the spin polarization. The finding of an intrinsic spin-polarization at the A-site cation observed in x-ray magnetic circular dichroism (XMCD) measurements also reveals the existence of a complex magnetic configuration at the interface, different from the magnetic phases observed at the inner layers.

Idioma: Inglés

DOI: 10.1063/1.5011172

Año: 2018

Publicado en: APPLIED PHYSICS LETTERS 112, 3 (2018), 032401 [5 pp]
ISSN: 0003-6951

Factor impacto JCR: 3.521 (2018)

Categ. JCR: PHYSICS, APPLIED rank: 31 / 148 = 0.209 (2018) - Q1 - T1

Factor impacto SCIMAGO: 1.331 - Physics and Astronomy (miscellaneous) (Q1)

Financiación: info:eu-repo/grantAgreement/EC/H2020/734187/EU/Spin conversion, logic storage in oxide-based electronics/SPICOLOST

Tipo y forma: Artículo (Versión definitiva)

Área (Departamento): Área Física Materia Condensada (Dpto. Física Materia Condensa.)