Ultrahigh refractive index sensitivity of TE-polarized electromagnetic waves in graphene at the interface between two dielectric media

TL;DR

This paper demonstrates that TE-polarized electromagnetic waves in graphene exhibit ultrahigh refractive index sensitivity at the interface of two dielectrics, enabling highly sensitive optical gas sensors with performance surpassing current technologies.

Contribution

It reveals the extreme sensitivity of TE waves in graphene to dielectric contrast changes and proposes a novel graphene-based optical gas sensor with superior detection limits.

Findings

TE waves are highly sensitive to dielectric contrast changes.

Ultrahigh refractive index sensitivity near zero imaginary conductivity.

Graphene sensor outperforms modern volume refractive index sensors.

Abstract

The behavior of the TE and TM electromagnetic waves in graphene at the interface between two semi-infinite dielectric media is studied. The dramatic influence on the TE waves propagation even at very small changes in the optical contrast between the two dielectric media is predicted. Frequencies of the TE waves are found to lie only in the window determined by the contrast. We consider this effect in connection with the design of graphene-based optical gas sensor. Near the frequency, where the imaginary part of the conductivity of graphene becomes zero, ultrahigh refractive index sensitivity and very low detection limit are revealed. The considered graphene-based optical gas sensor outperforms characteristics of modern volume refractive index sensors by several orders of magnitude.