Perfect reflection of chiral fermions in gated graphene nanoribbons.

Andreev reflection in graphene nanoribbons

We study Andreev reflection in graphene nanoribbon/superconductor hybrid junctions. By using a tightbinding approach and the scattering formalism we show that finite-size effects lead to notable differences with respect to the bulk-graphene case. At subgap voltages, conservation of pseudoparity, a quantum number characterizing the ribbon states, yields either a suppression of Andreev reflection...

Interplay between symmetry and spin-orbit coupling on graphene nanoribbons

We study the electronic structure of chiral and achiral graphene nanoribbons with symmetric edges, including curvature and spin-orbit effects. Curved ribbons show spin-split bands, whereas flat ribbons present spin-degenerate bands. We show that this effect is due to the breaking of spatial inversion symmetry in curved graphene nanoribbons, while flat ribbons with symmetric edges possess an inv...

High-κ oxide nanoribbons as gate dielectrics for high mobility top-gated graphene transistors

Deposition of high-κ dielectrics onto graphene is of significant challenge due to the difficulties of nucleating high quality oxide on pristine graphene without introducing defects into the monolayer of carbon lattice. Previous efforts to deposit high-κ dielectrics on graphene often resulted in significant degradation in carrier mobility. Here we report an entirely new strategy to integrate hig...

Interactions and screening in gated bilayer graphene nanoribbons

Unraveling the Electronic Structure of Narrow Atomically Precise Chiral Graphene Nanoribbons

Recent advances in graphene-nanoribbon-based research have demonstrated the controlled synthesis of chiral graphene nanoribbons (chGNRs) with atomic precision using strategies of on-surface chemistry. However, their electronic characterization, including typical figures of merit like band gap or frontier band's effective mass, has not yet been reported. We provide a detailed characterization of...