Charge pumping in monolayer graphene driven by a series of time-periodic potentials

TL;DR

This paper investigates quantum charge pumping in monolayer graphene using Floquet scattering-matrix formalism, revealing how time-periodic potentials can generate a nonzero dc current and induce anisotropic transmission.

Contribution

It introduces a theoretical analysis of quantum pumping in graphene with multiple time-periodic potentials, highlighting symmetry breaking and anisotropic effects.

Findings

Harmonic modulated potentials break time reversal symmetry.

Proper dynamic parameters enable nonzero dc pumped current.

Transmission becomes anisotropic with incident angle.

Abstract

We applied the Floquet scattering-matrix formalism to studying the electronic transport properties in a mesoscopic Dirac system. Using the method, we investigate theoretically quantum pumping driven by a series of time-periodic potentials in graphene monolayer both in the adiabatic and non-adiabatic regimes. Our numerical results demonstrate that adding harmonic modulated potentials can break the time reversal symmetry when no voltage bias is applied to the graphene monolayer. Thus, when the system is pumped with proper dynamic parameters, these scatterers can produce a nonzero dc pumped current. We also find that the transmission is anisotropic as the incident angle is changed.