Geometric magnetoconductance dips by edge roughness in graphene nanoribbons

TL;DR

This paper investigates how edge roughness affects magnetoconductance dips in graphene nanoribbons, revealing a threshold for observable effects related to edge disorder and current distribution.

Contribution

It demonstrates the impact of edge roughness on magnetoconductance dips in graphene nanoribbons through numerical simulations, highlighting the role of edge disorder and current density.

Findings

Magnetoconductance dips occur at cyclotron radii near ribbon width.

Edge roughness threshold influences the visibility of dips in zigzag nanoribbons.

Reduced edge current density affects the emergence of magnetoconductance features.

Abstract

The magnetoconductance of graphene nanoribbons with rough zigzag and armchair edges is studied by numerical simulations. nanoribbons with sufficiently small bulk disorder show a pronounced magnetoconductance minimum at cyclotron radii close to the ribbon width, in close analogy to the wire peak observed in conventional semiconductor quantum wires. In zigzag nanoribbons, this feature becomes visible only above a threshold amplitude of the edge roughness, as a consequence of the reduced current density close to the edges.