Speaker
Prof.
Jose Enrique Ortega
(Universidad del País Vasco)
Description
High-temperature deposition of rare-earths (RE) on noble metal surfaces, such as Au(111), gives rise to stable, REAu2 mono and bilayers of high crystalline quality. These surface alloys exhibit characteristic, long-range moiré patterns that can be utilized as growth templates [1]. In fact, cobalt deposition on such pre-patterned REAu2/Au(111) surfaces leads to self-organization of Co nano-dots. Depending on the RE material of the surface one can achieve different interactions that determine the magnetic properties of the dots arrays. In order to investigate the magnetic properties of the REAu2/Au(111) support and the Co/REAu2/Au(111) arrays, a detailed study combining X-ray Circular Magnetic Dichroism and Scanning Tunneling Microscopy was carried out. Several substrates were analyzed (SmAu2, GdAu2, and YbAu2), which share the same RE-Au2 surface structure and lattice constant, but reveal ferromagnetic, anti-ferromagnetic [2], and non-magnetic interactions with the Co nano-dot array, respectively. These interactions not only determine the magnetic properties below the Curie temperature TC of the substrate but also far above TC and lead to enhancements of the magnetic anisotropy and blocking temperature of the Co nano-dot array.
References
[1] M. Corso, L. Fernández, F. Schiller, and J. E. Ortega, ACS-Nano 4, 1603 (2010).
[2] L. Fernández, M. Blanco-Rey, M. Ilyn, L. Vitali, A. Correa, P. Ohresser, J.E. Ortega, A. Ayuela, and F. Schiller, Nano Letters 14, 2977 (2014).
Primary author
Dr
Frederik Schiller
(Centro de Física de Materiales CSIC)
Co-authors
Ms
Ana Magaña
(Universidad del País Vasco)
Prof.
Jose Enrique Ortega
(Universidad del País Vasco)
Dr
Laura Fernández Gómez-Recuero
(Donostia International Physics Center DIPC)
Dr
Max Ilyn
(Centro de Física de Materiales CSIC)
