doi:10.4028/www.scientific.net/SSP.257.60engRubín, J.Figueroa, A. I.Stankiewicz, J.Bartolomé, F.García, L. M.Cezar, J. C.Petroff, F.Deranlot, C.Bartolomé, J.Perpendicular magnetic anisotropy and intralayer interactions in a single layer of CoPt nanoparticlesART-2017-97106The multilayer films Al2O3/tCo Co/tPt Pt]N, produced by sequential deposition of Co and Pt on alumina consist in layers of CoPt alloyed nanoparticles. They show perpendicular magnetic anisotropy (PMA) below a freezing temperature Tf, an asperomagnetic-like phase below that temperature, and hard ferromagnetic ordering below a transition temperature T1 < Tf. A single layer granular film (N = 1) with deposition thicknesses tCo=0.7 nm, tPt=1.5 nm and particle diameter of 3 nm is presently studied. SQUID magnetometry shows that a single layer presents the three phases as well. Para-, aspero-and ferromagnetic phases are observed upon lowering the temperature, with transition temperatures Tf ˜ 375 K and T1 ˜ 200 K, respectively. In addition, the PMA persists, proving that there is no interlayer coupling in the multilayer system. SQUID results also reveal a core-shell structure in the CoPt nanoparticles.2017http://zaguan.unizar.es/record/7910710.4028/www.scientific.net/SSP.257.60http://zaguan.unizar.es/record/79107oai:zaguan.unizar.es:79107info:eu-repo/grantAgreement/ES/DGA/IMANA-E34info:eu-repo/grantAgreement/ES/MINECO/MAT2014-53921-RSOLID STATE PHENOMENA 257 (2017), 60-63All rights reservedhttp://www.europeana.eu/rights/rr-f/info:eu-repo/semantics/openAccess