Open AccessDielectric film sensing with TE mode of terahertz guided-mode resonance
Author(s) -
Hyeon Sang Bark,
Tae-In Jeon
Publication year - 2018
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.26.034547
Subject(s) - materials science , terahertz radiation , dielectric , optics , guided mode resonance , resonance (particle physics) , grating , optoelectronics , transverse mode , absorption (acoustics) , diffraction grating , composite material , physics , laser , particle physics
Guided-mode resonance (GMR) filters were implemented by combining a monolayer grating made of polyethylene terephthalate (PET) and a slab waveguide (dielectric film) made of quartz, PET, and Teflon. The terahertz (THz) GMRs were measured and simulated for films with thickness change from 0 to 500 µm. As the thickness increased, the transverse-electric (TE) mode such as TE 0,1 , TE 1,1 , TE 2,1 , and TE 3,1 appeared sequentially. Because the magnitude and frequency of the GMRs depend on the films' absorption and thickness, we applied GMRs in order to sense the film's thickness of the film. When the GMR filter was measured, resonance depth and frequency changes according to the film thickness were much more sensitive than they were when only the film was measured using THz time-domain spectroscopy (THz-TDS).