Perfect Reflection of Chiral Fermions in Gated Graphene Nanoribbons

TL;DR

This paper presents a theoretical study showing that, contrary to expectations, chiral fermions in gated graphene nanoribbons can undergo perfect reflection under certain conditions, which could be experimentally observed.

Contribution

It reveals a novel phenomenon of perfect reflection of chiral fermions in armchair graphene nanoribbons, challenging the analogy with quantum field theory predictions.

Findings

Perfect reflection of chiral fermions in specific gated configurations

Potential experimental observation in narrow graphene constrictions

Contradicts the expected perfect transmission predicted by quantum field theory

Abstract

We describe the results of a theoretical study of transport through gated metallic graphene nanoribbons using a non-equilibrium Green function method. Although analogies with quantum field theory predict perfect transmission of chiral fermions through gated regions in one dimension, we find \emph{perfect reflection} of chiral fermions in armchair ribbons for specific configurations of the gate. This effect should be measurable in narrow graphene constrictions gated by a charged carbon nanotube.