A tunable plasmonic refractive index sensor with nanoring-strip graphene arrays

TL;DR

This paper presents a numerically studied, tunable plasmonic refractive index sensor using nanoring-strip graphene arrays, demonstrating large sensing range, angle insensitivity, and potential for biosensing applications.

Contribution

It introduces a novel design of graphene nanoring-strip arrays for tunable plasmonic sensing with angle-insensitive resonance properties.

Findings

Large sensing range achieved by changing the medium's refractive index.

Transmission characteristics can be flexibly adjusted via doping levels.

Resonance remains stable across a wide incidence angle range for both polarizations.

Abstract

In this paper, a tunable plasmonic refractive index sensor with nanoring-strip graphene arrays is numerically investigated by the finite difference time domain (FDTD) method. The simulation results exhibit that by changing the sensing medium refractive index nmed of the structure, the sensing range of the system is large. By changing the doping level ng, we noticed that the transmission characteristics can be adjusted flexibly. The resonance wavelength remains entirely the same and the transmission dip enhancement over a big range of incidence angles [0,45] for both TM and TE polarizations, which indicates that the resonance of the graphene nanoring-strip arrays is insensitive to angle polarization. The above results are undoubtedly a new way to realize various tunable plasmon devices, and may have a great application prospect in biosensing, detection and imaging.