Tunable asymmetric transmission of THz wave through a graphene planar chiral structure

TL;DR

This paper demonstrates tunable asymmetric transmission of circularly polarized terahertz waves through a graphene planar chiral structure, revealing enantiomeric sensitivity influenced by the Fermi level, with potential applications in polarization devices.

Contribution

It introduces a graphene-based planar chiral structure exhibiting tunable asymmetric THz wave transmission, expanding understanding of light-matter interactions in chiral nanostructures.

Findings

Asymmetric transmission observed in graphene nanostructures.

Transmission difference varies with Fermi level.

Potential for polarization-sensitive device applications.

Abstract

In this letter, we show that asymmetric transmission of circularly polarized waves through a nanostructured planar chiral graphene film can be observed in terahertz range. The asymmetric transmission effect of monatomic layer graphene closely resembles that of metallic planar chiral nanostructures which has previously been demonstrated. And the relative enantiomeric difference in the total transmission varies with the change of graphene's Fermi level. The plasmonic excitation in the graphene nanostructure is the enantiometically sensitive which is asymmetric for opposite propagating directions. This phenomenon will deepen our understanding of light-matter interactions in planar chiral structures and may find applications in polarization-sensitive devices, sensors, detectors and other areas.