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arXiv · 2309.15663

Disclosing the nature of asymmetric interface magnetism in Co/Pt multilayers

Adriano Verna·Paola Alippi·Francesco Offi·Gianni Barucca·Gaspare Varvaro·Elisabetta Agostinelli·Manfred Albrecht·Bogdan Rutkowski·Alessandro Ruocco·Daniele Paoloni·Manuel Valvidares·Sara Laureti
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Abstract

Nowadays a wide number of applications based on magnetic materials relies on the properties arising at the interface between different layers in complex heterostructures engineered at the nanoscale. In ferromagnetic/heavy metal multilayers, such as the [Co/Pt]$_N$ and [Co/Pd]$_N$ systems, the magnetic proximity effect was demonstrated to be asymmetric, thus inducing a magnetic moment on the Pt(Pd) layer that is typically higher at the top Co/Pt(Pd) interface. In this work, advanced spectroscopic and imaging techniques were combined with theoretical approaches to clarify the origin of this asymmetry both in Co/Pt trilayers and, for the first time, in multilayer systems that are more relevant for practical applications. The different magnetic moment induced at the Co/Pt interfaces was correlated to the microstructural features, which are in turn affected by the growth processes that induce a different intermixing during the film deposition, thus influencing the interface magnetic profile.

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Adriano Verna, Paola Alippi, Francesco Offi, Gianni Barucca, Gaspare Varvaro, Elisabetta Agostinelli, Manfred Albrecht, Bogdan Rutkowski, Alessandro Ruocco, Daniele Paoloni, Manuel Valvidares, Sara Laureti. 2023-09-27. Disclosing the nature of asymmetric interface magnetism in Co/Pt multilayers. https://doi.org/10.1021/acsami.1c22341

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