Effects of Strain on Notched Zigzag Graphene Nanoribbons

Abstract

The combined effects of an asymmetric (square or V-shaped) notch and uniaxial strain are studied in a zigzag graphene nanoribbon (ZGNR) device using a generalized tight-binding model. The spin-polarization and conductance-gap properties, calculated within the Landauer-Büttiker formalism, were found to be tunable for uniaxial strain along the ribbon-length and ribbon-width for an ideal ZGNR and square (V-shaped) notched ZGNR systems. Uniaxial strain along the ribbon-width for strains ≥10% initiated significant notch-dependent reductions to the conduction-gap. For the V-shaped notch, such strains also induced spin-dependent changes that result, at 20% strain, in a semi-conductive state and metallic state for each respective spin-type, thus demonstrating possible quantum mechanisms for spin-filtration.

Tuning the band structure of graphene nanoribbons through defect-interaction-driven edge patterning

“…It should be mentioned that edge defects of similar nature with the V-shaped GNR edge pattern features of the present work also have been studied broadly in the literature [42][43][44][45] , with the understanding that our work emphasizes on the formation of these GNR edge patterns as a result of pore-edge (and generally defect-edge) interactions. In particular, we mention that previous studies have also shown that an interplay of zigzag and armchair edges in GNRs may lead to significant changes in the electronic structure of the material 37,38 .…”