Open AccessEnhancement of THz resonance using a multilayer slab waveguide for a guided-mode resonance filter
Author(s) -
Sung Bo Lee,
Hyeon Sang Bark,
Tae-In Jeon
Publication year - 2019
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.27.029357
Subject(s) - materials science , guided mode resonance , resonance (particle physics) , q factor , refractive index , transmittance , monolayer , slab , absorption (acoustics) , optics , grating , optoelectronics , antiresonance , attenuation , resonator , composite material , diffraction grating , nanotechnology , physics , particle physics , geophysics , geology , piezoelectricity
We propose a multilayer slab waveguide (SWG) to enhance the resonance of the transmittance with a guided-mode resonance (GMR) filter. The resonance characteristics of the GMR filter were studied in three types according to the method of attaching the grating film to a SWG, which consists of 25 µm thick polyethylene terephthalate (PET) film layers separated by 25 µm air layers. The resonance depth with the multilayer SWG was improved over that of the monolayer SWG because the refractive index and absorption of the multilayer SWG were reduced. However, because resonance with a high Q-factor in the monolayer SWG has a large attenuation loss due to material absorption, the resonance enhancement was insufficient even for the multilayer SWG. We were able to make the resonance depth up to 5.2 times larger than the monolayer SWG in the TE 1,1 mode using a five-layer SWG. We verified the enhancements with the multilayer SWG using a finite-difference frequency-domain (FDFD) simulation.