  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.
