Effect of magnetic field on fermions in graphene through time-oscillating potential

TL;DR

This paper investigates how a time-oscillating scalar potential and magnetic field influence Dirac fermions in graphene, revealing additional energy subbands and oscillating current densities through Floquet theory analysis.

Contribution

It introduces a novel analysis of Dirac fermions in graphene under combined magnetic and oscillating potentials using Floquet theory, highlighting new subband structures and current behaviors.

Findings

Extra subbands in energy spectrum due to oscillating potential

Current density depends strongly on magnetic field and potential

Energy spectrum exhibits symmetry and oscillating current densities

Abstract

We study the effect of a magnetic field on Dirac fermions in graphene subject to a scalar potential oscillating in time. Using the Floquet theory and resonance approximation, we show that the energy spectrum exhibits extra subbands resulted from the oscillating potential in addition to quantized Landau levels. It is found that a current density can be generated in $ x $ and $ y $-directions that is strongly dependent on the magnetic field and potential. Our numerical analysis show that the energy spectrum possesses a symmetry and the current density oscillates with different amplitudes under various conditions.