Fabry-Perot and Aharonov-Bohm interference in ideal graphene nanoribbons

TL;DR

This paper investigates quantum interference effects in ideal graphene nanoribbons, predicting Fabry-Perot and Aharonov-Bohm oscillations in conductance due to electron scattering and quasi-bound states, with implications for nanoelectronic device design.

Contribution

It provides a comparative theoretical analysis of Fabry-Perot and Aharonov-Bohm interference effects in graphene nanoribbons considering Coulomb interactions.

Findings

Fabry-Perot oscillations predicted in noninteracting theory.

Aharonov-Bohm interference dominates when Coulomb interactions are included.

Quasi-bound states form inside the ribbon, causing conductance resonances.

Abstract

Quantum-mechanical calculations of electron magneto-transport in ideal graphene nanoribbons are presented. In noninteracting theory, it is predicted that an ideal ribbon that is attached to wide leads should reveal Fabry-Perot conductance oscillations in magnetic field. In the theory with Coulomb interaction taken into account, the oscillation pattern should rather be determined by the Aharonov-Bohm interference effect. Both of these theories predict the formation of quasi-bound states, albeit of different structures, inside the ribbon because of strong electron scattering on the interfaces between the connecting ribbon and the leads. Conductance oscillations are a result of resonant backscattering via these quasi-bound states.