T. Nakajima and K. Shintani
Suspended graphene nanoribbons (GNRs), which are used in electronic devices (transistors, mass sensors, dust detectors, etc.) to connect terminals like bridges, can be treated as edge-constrained GNRs. In the article by Nakajima and Shintani (pp. 2839-2847), edge-constrained GNRs of various sizes and initial strains are studied using molecular dynamics (MD) simulations. To induce strain in the GNRs, the bond lengths between carbon atoms of the initial configurations of the GNR models are varied.
The cover image shows snapshots of GNRs with free armchair edges (left) and free zigzag edges (right) in MD simulation. The out-of-plane deformations are exaggerated tenfold, the short edges are constrained. The GNRs are under various uniaxial strains: the top-left GNR is under a small compressive strain and the top-right GNR under no strain, whereas the other GNRs from top to bottom are under gradually-increased tensile strain. As shown, the GNR under compressive strain buckles. On the other hand, ripples appear under tensile strain. With increasing tensile strain, the height of the ripples decreases and their longitudinal wavelength increases, reaching about 20 nm under large strain (bottom images). These figures suggest that the out-of-plane deformations of constrained GNRs can be controlled by imposing strains.