Open AccessExcitation of graphene surface plasmons polaritons by guided-mode resonances with high efficiency
Author(s) -
Yuxiang Ren,
Xuguang Guo,
Guixue Zhang,
A. V. Balakin,
Alexander P. Shkurinov,
Anqi Yu,
Yiming Zhu
Publication year - 2020
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.391237
Subject(s) - surface plasmon polariton , materials science , surface plasmon , graphene , polariton , grating , optics , excitation , guided mode resonance , waveguide , dielectric , plasmon , optoelectronics , diffraction grating , physics , nanotechnology , quantum mechanics
An Otto-like configuration for the excitation of graphene surface plasmon polaritons (GSPPs) is proposed. The configuration is composed of a metallic grating-dielectric-waveguide structure and a monolayer graphene with a subwavelength vacuum gap between them. The evanescent field located at the bottom surface of the dielectric waveguide corresponding to grating-coupled guided-mode resonances (GMRs) is utilized to efficiently excite the highly conned GSPPs. The finite difference time domain method is used to investigate the behaviors of the GMR-GSPP hybrid modes. The dispersion relations of GMRs and GSPPs are calculated and the numerical results further identify the excitation of GMR-GSPP hybrid modes. By changing the gap between the graphene layer and the bottom of the dielectric waveguide and the Fermi energy of graphene, the resonant frequencies of GMR-GSPP hybrid modes can be continuously tuned. When the optimized excitation condition is satisfied, the maximum energy enhancement factor in the gap can reach about 500 at the resonant frequencies. The proposed structure can be used to realize highly sensitive, compatible with planar fabrication technology, and electrically (mechanically) tunable sensors.