Transmission Properties of Periodic Metal/Dielectric Hole Array and Its Application to Narrow Bandwidth Infrared Thermal Emitter
Date Issued
2007
Date
2007
Author(s)
Tsai, Ming-Wei
DOI
en-US
Abstract
The interaction of surface plasmon polartions on a periodic array of metal holes is investigated in theory and experiment. Extraordinary transmission through a silver film perforated with square shaped hole arrays in a square lattice was demonstrated. When the squared hole size is close to a half lattice constant a/2, the split of the degenerate (±1,0) Ag/Si and (0,±1) Ag/Si modes into two peaks becomes apparent. SPPs dispersion relations demonstrate the photonic bandgap opens up when the size of the squared hole exceeds a half lattice constant a/2. Extraordinary transmission through a silver film perforated with rectangular shaped hole arrays in a square lattice was demonstrated. Additionally, the SP dispersion relations of the square hole array with different aspect ratios of holes were measured that demonstrate that the LSPs were created by the coupling of surface plasmons between the edges of the rectangular holes. Various narrow bandwidth infrared light sources are reported. This triple layer Ag/SiO2/Ag structure, with top Ag layer is perforated by hexagonal-arranged hole arrays, exhibit narrow bandwidth emission that comes (1,0) Ag/SiO2 degenerate modes. Its reflection dispersion relation with different SiO2 thicknesses shows that when the SiO2 layer is thin, SPPs induced from top metal plate are strongly coupled with the bottom metal that causes the increasement of the effective refractive index of SiO2 which reshifts the emission wavelength. Two-colored plasmonic thermal emitters are fabricated successfully. Two emission peaks from Ag/SiO2 and Ag/Air SPPs can be clearly seen. It was demonstrated that when the central SiO2 layer of the sandwiched structure is flat without holes, the emission spectrum is narrower than that of the perforated one. Metal/SiO2/metal trilayer thermally generated infrared emitters with different top and bottom periodic metal arrangements were fabricated and their emission spectra were measured. It is found that the top surface plasmon converted to light radiation directly, whereas the bottom surface plasmon can radiate out when its emission peak position matches that of the top surface plasmon. A suitable designed trilayer Ag/SiO2/Au thermal emitter can be used as the narrow bandwidth infrared light source. The use of Au instead of Ag as bottom metal layer is because Au can sustain the high temperature deposition of SiO2 by plasma enhanced chemical vapor deposition. When the SiO2 layer is thick enough, cavity mode resonance exist, which is generated in the SiO2 layer between two metal film regard as a waveguide and varies with the SiO2 layer thickness. The hybrid cavity/surface plasmon mode is influenced by the film thickness and the periodicity of top Ag film.
Subjects
表面電漿
紅外線
黑體輻射
光源
異常穿透
surface plasmon
infrared
blackbody
emitter
light source
extraordinary transmission
Type
thesis
File(s)![Thumbnail Image]()
Loading...
Name
ntu-96-D92943020-1.pdf
Size
23.31 KB
Format
Adobe PDF
Checksum
(MD5):83bce2dfdcc66b2c9e74d2bcfc71e788