Enhanced Faraday rotation and magneto-optical figure of merit in gold grating/graphene/silicon hybrid magneto-plasmonic devices

Jun Qin,Tingting Tang,Ke Jia,Haipeng Lu,Shuang Xia,Li Zhang,Peiheng Zhou,Bo Peng,Longjiang Deng,Chuangtang Wang,Lei Bi

doi:10.1063/1.5008775

Jun Qin, Tingting Tang + Show 9 more

Open Access

PDF Available

https://doi.org/10.1063/1.5008775

Copy DOI

Export

Save

Cite

Abstract
Highlights/Summary
Full-Text PDF
Similar Papers

Abstract

Listen

Graphene is a promising THz magneto-optical material. However, high Faraday rotation is only achievable at a low THz frequency range in single layer graphene. In this paper, we report simultaneous Faraday rotation and optical transmission enhancement in Au grating/graphene/silicon hybrid plasmonic structures across a wide frequency range from 0.43 to 24 THz using extraordinary transmission of THz spoof surface plasmons. In a broad frequency range up to 13.1 THz, the Faraday rotation and magneto-optical figure of merit in this hybrid structure can exceed the maximum value of single layer graphene at the low THz frequency range. Numerical analysis on the device dispersion relation indicates that the mechanism of simultaneous Faraday rotation and transmission enhancement is due to coupling of the TE waveguide mode with the TM hybrid waveguide-plasmon mode. Our work demonstrates the hybrid plasmonic structure as a promising candidate for THz nonreciprocal photonic device applications.

Highlights

Crystals[15,16,17] to enhance the light-matter interaction
We theoretically demonstrate that a heterostructure of Au grating/Single layer graphene (SLG)/Si can simultaneously yield high Faraday rotation angle and optical transmission in THz
Thanks to the enhanced light-mater interaction using Au spoof surface plasmons (SSPs), we demonstrate high Faraday rotation angle and figure of merit (FOM) in a wide frequency range of 0.43–24 THz

Summary

Introduction

Crystals[15,16,17] to enhance the light-matter interaction. due to the single atomic layer thickness and low carrier density in graphene, the oscillator strength of graphene magnetoplasmonic resonance is low, leading to reduced Faraday rotation and higher scattering loss at high THz frequency range, whereas photonic crystal structures usually require multilayer thin films and relatively complex device structures. Enhanced Faraday rotation and magnetooptical figure of merit in gold grating/ graphene/silicon hybrid magnetoplasmonic devices

Results

Conclusion