Bistability of zigzag edge magnetism in graphene nanoribbons induced by electric field

Electric field effects in zigzag edged graphene nanoribbons

We investigate the magnetic ordering in zigzag edged graphene nanoribbons under cross-ribbon electric fields by using the Hubbard model within the unrestricted Hatree-Fock approximation. In the absence of applied electric field, the ground state is an “edge-magnetized state” with magnetic moments mainly localized on the edges, where the moments on the two edges are mutually antiparallel. Under ...

Preserving the Edge Magnetism of Zigzag Graphene Nanoribbons by Ethylene Termination: Insight by Clar's Rule

By means of density functional theory computations, we demonstrated that C2H4 is the ideal terminal group for zigzag graphene nanoribbons (zGNRs) in terms of preserving the edge magnetism with experimental feasibility. The C2H4 terminated zGNRs (C2H4-zGNRs) with pure sp(2) coordinated edges can be stabilized at rather mild experimental conditions, and meanwhile reproduce the electronic and magn...

Limited robustness of edge magnetism in zigzag graphene nanoribbons with electrodes.

It is shown that apart from well-known factors, like temperature, substrate, and edge reconstruction effects, also the presence of external contacts is destructive for the formation of magnetic moments at the edges of graphene nanoribbons (GNRs). The edge magnetism gradually decreases when graphene/electrode interfaces become more and more transparent for electrons. In addition to the graphene/...

Stability of edge states and edge magnetism in graphene nanoribbons

Jens Kunstmann,1,* Cem Özdoğan,2 Alexander Quandt,3,4 and Holger Fehske3 1Institute for Materials Science, TU Dresden, Hallwachstr. 3, D-01069 Dresden, Germany 2Department of Materials Science and Engineering, Çankaya University, Balgat, TR-06530 Ankara, Turkey 3Institut für Physik der Universität Greifswald, Felix–Hausdorff-Str. 6, D-17489 Greifswald, Germany 4School of Physics and DST/NRF Cen...

Effect of random edge-vacancy disorder in zigzag graphene nanoribbons