Beating oscillation and Fano resonance in the laser assisted electron transmission through graphene {\delta}- function magnetic barriers

TL;DR

This paper theoretically studies electron transmission through graphene with magnetic barriers under laser illumination, revealing controllable beating oscillations and Fano resonances that could inform optoelectronic device design.

Contribution

It introduces a non-perturbative Floquet approach to analyze laser-assisted electron transmission, demonstrating controllable oscillation patterns and resonances in graphene magnetic barriers.

Findings

Laser field induces beating oscillations in transmission.

Fano resonances appear at small inter barrier distances.

Laser intensity controls oscillation and resonance features.

Abstract

We investigate theoretically the transmission of electrons through a pair of {\delta}- function magnetic barriers in graphene in presence of external monochromatic, linearly polarised and CW laser field. The transmission coefficients are calculated in the framework of non-perturbative Floquet theory using the transfer matrix method. It is noted that the usual Fabry-Perot oscillations in transmission through the graphene magnetic barriers with larger inter barrier separation takes the shape of beating oscillations in presence of the external laser field. The laser assisted transmission spectra are also found to exhibit the characteristic Fano resonances (FR) for smaller values of the inter barrier separation. The appearance of the perfect node in the beating oscillation and the asymmetric Fano line shape can be controlled by varying the intensity of the laser field. The above features could provide some useful and potential information about the light - matter interactions and may be utilized in the graphene based optoelectronic device applications.