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Topological Metal-Insulator Transition in Narrow Graphene Nanoribbons?

revised on 27.08.2020 and posted on 27.08.2020 by Aristides Zdetsis, Eleftherios Economou
We show that very narrow armchair graphene nanoribbons (AGNRs) of length L and width of 2 zigzag-rings undergo a metal-insulator-like transition at a critical length of 10nm, where the energy gap drops rather abruptly, and the conductivity, estimated, through an invoked computational scheme, rises almost discontinuously to a value between that of a perfect quasi one-dimensional system, and the nominal minimum conductivity of graphene. At this length, the aromatic and non-aromatic rings are interchanged, and sharp peaks appear in the density of states around the Fermi level, suggesting metallic-like behaviour. Such peaks linked to edge states at the Dirac point(s) coincide with the charge-neutrality point(s), associated with the minimum conductivity of graphene. Thus, we have an uncommon combination of interrelated “short-long”, “core-edge,” topological-aromatic transition(s) due to strong quantum confinement, driven by inversion symmetry conflict. The bandgap decreases with the 2/3 power of length before the “transition” and logarithmically afterwards. These effects are practically non-existent for wider AGNRs


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Email Address of Submitting Author


University of Patras Department of Physics



ORCID For Submitting Author


Declaration of Conflict of Interest

There is no conflict of interest

Version Notes

This is 2nd versions


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