Graphene-based systems for spintronics: Magnetic interactions at the graphene/3d metal interface SpinGraph

• Antragsteller: Professor Dr. Mikhail Fonin; Professor Karsten Horn, Ph.D.
• Fachliche Zuordnung: Experimentelle Physik der kondensierten Materie
• Förderung: Förderung von 2010 bis 2013
• Projektkennung: Deutsche Forschungsgemeinschaft (DFG) - Projektnummer 162780737

The specific properties of graphene in its interaction with metallic, and in particular ferromagnetic, materials are at the centre of research activities of the present proposal. The long electronic mean free path and negligible spin-orbit coupling in graphene lead to large spin relaxation times and make graphene an ideal material for ballistic spin transport. The interaction with magnetic substrates thus makes the graphene-ferromagnet interface a viable system for the realization of spin field-effect transistors (spin FET), based on the manipulation of the spin of an injected electron solely via the application of an electric field. Such applications as spin filters and spin FETs have been recently at the focus of many theoretical investigations, but almost no experimental work exists at present. These transport properties are strongly influenced by the specific atomic environment, effects which need to be studied in detail. Theoretical predictions indicate that graphene itself, while nonmagnetic as an extended “2D solid”, may actually acquire a magnetic moment at structural and chemical defects, namely at the edge of so-called nanoribbons, or in graphene decorated with defect sites, such as hydrogen, but no experimental verification exists. Finally, graphene may provide, in a more applied context, an ideal means to chemically passivate magnetic layers, or to provide a “nanomesh” template for the creation of ordered arrays of magnetic nanoclusters, of possible interest for high density data storage. In order to contribute to an understanding of graphene/3d-metal systems in the context of (i) inert spin-filtering devices and spin valves, and (ii) high-density magnetic storage devices, the work program is split into two strongly interlinked main topics. They also involve a continuation of ongoing research on the fundamental physical properties of graphene, with the main research focus shifting towards the investigation of the electronic and magnetic properties of hybrid graphene/3d-metal systems.

• DFG-Verfahren: Sachbeihilfen
• Internationaler Bezug: Italien, Österreich, Schweiz
• Beteiligte Personen: Professor Dr. Harald Brune; Dr. Carlo Carbone; Privatdozent Dr. Yuriy Dedkov; Professor Dr. Josef Redinger