Vlaic, SergioMousadakos, DimitrisOuazi, SafiaRusponi, StefanoBrune, Harald2022-02-282022-02-282022-02-282022-02-0110.3390/nano12030518https://infoscience.epfl.ch/handle/20.500.14299/185871WOS:000756123200001The magnetic properties and the atomic scale morphology of bimetallic two-dimensional nanoislands, epitaxially grown on fcc(111) metal surfaces, have been studied by means of Magneto-Optical Kerr Effect and Scanning Tunneling Microscopy. We investigate the effect on blocking temperature of one-dimensional interlines appearing in core-shell structures, of two-dimensional interfaces created by capping, and of random alloying. The islands are grown on Pt(111) and contain a Co-core, surrounded by Ag, Rh, and Pd shells, or capped by Pd. The largest effect is obtained by Pd capping, increasing the blocking temperature by a factor of three compared to pure Co islands. In addition, for Co-core Fe-shell and Co-core FexCo1-x-shell islands, self-assembled into well ordered superlattices on Au(11,12,12) vicinal surfaces, we find a strong enhancement of the blocking temperature compared to pure Co islands of the same size. These ultra-high-density (15 Tdots/in(2)) superlattices of CoFe nanodots, only 500 atoms in size, have blocking temperature exceeding 100 K. Our findings open new possibilities to tailor the magnetic properties of nanoislands.Chemistry, MultidisciplinaryNanoscience & NanotechnologyMaterials Science, MultidisciplinaryPhysics, AppliedChemistryScience & Technology - Other TopicsMaterials SciencePhysicsblocking temperaturenanoislandstransition metalsmagnetic susceptibilitymagneto-optical kerr effectscanning tunneling microscopynucleationreversalpt/coatoms3dtext::journal::journal article::research article