Band filling effects on the emergence of magnetic skyrmions: Pd/Fe and Pd/Co bilayers on Ir(111)

Structurally similar transition metal systems can exhibit very different magnetic properties. An instructive example is the widely studied Pd/Fe/Ir(111) multilayer, which shows a spin-spiral ground state, while Pd/Co/Ir(111) presents a ferromagnetic (single-domain) ground state. Here, the authors analyze the origin of this difference combining $a\phantom{\rule{0}{0ex}}b$ $i\phantom{\rule{0}{0ex}}n\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}t\phantom{\rule{0}{0ex}}i\phantom{\rule{0}{0ex}}o$ and atomistic spin-dynamics calculations, demonstrating that the distinct behaviors can be explained by a simple rigid-band-like model. This analysis highlights the possibility of tuning topological magnetic structures by alloying and/or external agents, e.g., electric fields.