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DESIGNING WEAVING PATTERN AND ENGINEERING MULTILAYER STRUCTURE OF NYLON-ACRYLIC FABRIC UTILIZING IN TRIBOELECTRIC NANOGENERATOR
(2025-01-01)
Navatragulpisit, Suchanat
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Krailadsirirattna, Praophansupa
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Khwanming, Rawiwan
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Pongampai, Satana
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Plaipichit, Suwan
In the contemporary era, the textile triboelectric nanogenerator (T-TENG) has sparked interest to be a powerful energy supply for small electronic devices and electronic component in next generation of electronic textiles. Most T-TENG is developed by adding other materials to fabric or cloths that probably limit the comfortable use. Fabrication of conformable fabrics with high triboelectric outputs remains challenging. This research is firmly focused on the development of fully-fabric T-TENG by employing woven nylon-acrylic fabrics as the main contact material and designing a weaving pattern together with engineering a multi-layered structure to amplify its electrical efficiency. Based on the experimental results, different weaving patterns provided different electrical output values owing to its different contact surface areas. The matt weave pattern can yield the best electrical output regarding the extreme deformations. A further significant enhancement in T-TENG’s performance is consistent with inserting polymer intermediate layer. Adding ball-fiber and kapok serves as a synergetic charge-trapping interlayer, rendering a high triboelectricity of both open circuit voltage (VOC) and short circuit current (ISC) for 3 to 8 times higher than that of nylon-acrylic single layer. Finally, the multilayer fabric T-TENG is integrated with the long-sleeved garments and provide output enough to fully-charge the 0.22 μF and 0.33 μF capacitors together with brightening 30 LEDs. Finally, this work demonstrates a potential way with simple procedures in achieving fully-fabric T-TENG for small-scale energy sources that can harvest biomechanical energy to power electronic component for approaching the real application in E-textile systems.
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Asymmetrical resonant cavity thin film devices designed for vanadium dioxide applications
(2025-01-01)
Padungatthakij, Chettanat
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Wicharn, Surawut
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Buranasiri, Prathan
Vanadium dioxide (VO2) is a volatile phase change material (PCM) that undergoes a rapid structure transition when heated above and reverts when cooled below its transition temperature. This transition alters its optical properties significantly when compared to normal materials, making it possible to design a thin film device with switching operation mode. In this paper, we redesign VO2-based devices with two different use cases to introduce an asymmetrical resonant cavity (AsymReca) structure. The redesigned process aimed to enhance the optical performance of the central VO2 layer and gave it an antireflection property. Using simulation, we discuss the advantages and limitations of this design approach and highlighting its potential use case.
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Evaluating Noise Reduction Methods for Raman Spectroscopy in Transmission and Reflection Configurations
(2024-05-01)
Sassuvun, Wasunun
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Buranasiri, Prathan
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Wicharn, Surawut
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Puttharugsa, Chokchai
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Limnonthakul, Puenisara
This work involved comparing Raman signals obtained from two different Raman spectroscopy configurations, using two distinct noise reduction methods. The excitation light source was a laser diode with a wavelength of 532 nm. A long-pass filter and focusing lens were utilized to block the excited light from the source and concentrate the Raman signals due to their weaker nature compared to the excited light signals. Light of 532 nm wavelength was blocked during green laser diode illumination using a long-pass filter. Two configurations were studied: transmission Raman spectroscopy (TRS) and reflection Raman spectroscopy (RRS). Raman signals from both configurations were compared, and the boxcar averaging and Vancouver Raman algorithm (VRA) noise reduction methods were investigated and compared. The results showed that Raman signals from the transmission configuration were higher than those from the reflection configuration, and noise signals were effectively reduced using both the boxcar averaging and VRA methods.
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Phase-change metamaterial for tunable polarization conversions in terahertz region
(2024-01-01)
Wicharn, Surawut
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Buranasiri, Prathan
In this study, a phase-change metamaterial (PCM) is proposed to be applied as tunable terahertz (THz) polarization converter. The structure of PCM consists of 4 layers such as hyperbolic medium (HM) layer, vanadium dioxide (VO2) layer, the polyimide (PI) layer, and gold (Au) gratings, respectively. The HM layer is made by two-dimensional arrangement of gold (Au) nanowires in x-y plane immerged in PI host slab. The polarization converting characteristics of PCM structure is investigated numerically by using anisotropic transfer-matrix method (ATMM). The numerical results show that, when the VO2 is in insulating state, the PCM structure provides transmitted cross-linear polarization conversion and when the VO2 is changed to conducting state, the PCM structure gives both reflective cross-linear polarization and linear-to-circular polarization conversions.
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Epsilon-near-zero phase-matching for second-harmonic generation in semiconductor-based nanowire hyperbolic metamaterial
(2023-01-01)
Wicharn, Surawut
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Buranasiri, Prathan
Hyperbolic metamaterials have been widely used for nonlinear optical applications. Their unique functionality for nonlinear optics enhancement due to the hyperbolic dispersion is induced by a strong shape anisotropy. In this work, we numerically investigated the second-harmonic generation (SHG) in two-dimensional periodic arrays of aluminium gallium arsenide (AlGaAs) nanowires embedded in ordered porous aluminum oxide (Al2O3) or the nanowire hyperbolic metamaterial (NHMM). Under local effective medium approximation, the homogenization of the NHMM was achieved due to deep sub-wavelength size of each nanowire radius. Then this medium was classified as an effective uniaxial medium with anisotropic electric permittivity. The NHMM provided the spectral position of second-harmonic (SH) wavelength, which is determined at the epsilon-near-zero (ENZ) by the optimal design of NHMM structural parameters such as AlGaAs radius or fill fraction. Consequently, a gigantic increment of SHG conversion efficiency was achieved because of dramatic phase-matching at ENZ point. This mechanism is attributed to electric field enhancement of SHG inside the metamaterial. According to numerical results, the NHMM can be applied as nonlinear frequency converters in integrated nanophotonic systems.
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Phase-matched second-harmonic generation in core-shell nanowire hyperbolic metamaterial
(2022-09-01)
Wicharn, Surawut
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Banerjee, Partha P.
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Buranasiri, Prathan
Second-harmonic generation is well-known nonlinear frequency conversion technique, which can be applied in nonlinear optical characterization of materials and all-optical signal processing. This phenomenon requires phase-matching to maximize the conversion efficiency of generated second-harmonic field. But the phase-matching condition is difficult to achieve because of dispersion of naturally existing materials. To overcome this limitation, we propose an innovative phase-matching technique, which is called hyperbolic phase-matching, that can be possibly achieved by managing dispersion of a hyperbolic metamaterial. Here, the hyperbolic metamaterial is made of two-dimensional periodic arrays of core-shell nanowires, which have aluminium gallium arsenide as a core and gold as a shell, immersed in anodic aluminium oxide matrix. We have demonstrated phase-matched conditions for two different non-collinear second-harmonic interacting configurations in the metamaterial, which can be created by tuning incident angle of pump field to optimal values. Finally, conversion efficiencies of transmitted and reflected second-harmonic pulses as a function of incident angle and input pulse intensity were examined. The maximum conversion efficiencies are obtained at optimal incident angle and largest pumping intensity.
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Recursive-formula for second-harmonic generation problem in photonic hypercrystal
(2022-09-01)
Buranasiri, Prathan
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Plaipichit, Suwan
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Puttharugsa, Chokchai
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Wicharn, Surawut
In this work, we proposed a recursive-formula based on transfer-matrix method to solve problem of second-harmonic generation by obliquely incident fundamental-harmonic wave in a photonic hypercrystal, which is composed of one-dimensional periodically alternating arrangement of nonlinear hyperbolic metamaterial layer with anisotropic permittivities: ε<inf>axx</inf>, ε<inf>azz</inf> and layer thickness: a and linear dielectric layer with isotropic permittivity: ε<inf>a</inf> and layer thickness: b. This proposed formula was very simple and accurate for calculating conversion efficiency of second-harmonic generation at various incident angles of fundamental-harmonic wave and thicknesses of nonlinear hyperbolic metamaterial layer. The numerical results showed that the maximum conversion efficiency can be achieved by the strong local field confinement of fundamental-harmonic wave in the photonic hypercrystal and phase-matching due to optimal values of hypercrystal layer thickness and incident angle of fundamental-harmonic wave.
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Phase Extracting Imaging by Stacking Defocus Transport of Intensity Equation
(2022-01-01)
Plaipichit, Suwan
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Visessamit, Jakkapol
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Wicharn, Surawut
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Buranasiri, Prathan
The investigation of cells was performed using TIE. The phase imaging using a stack of low defocus intensity images has shown better results of the cell edge and shape comparing with the traditional one.
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Hybrid nanowire-hyperbolic metamaterial based broadband absorber for the visible and near-infrared regions
(2021-12-01)
Buranasiri, Prathan
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Plaipichit, Suwan
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Puttharugsa, Chokchai
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Wicharn, Surawut
In this work, spectral absorbance of hybrid nanowire-hyperbolic metamaterial was investigated numerically by using transfer-matrix method. The hybrid nanowire-hyperbolic metamaterial is consisted of two-dimensional periodically arranged arrays of subwavelength-sized hybrid nanowires (with circular cross-section) embedded in silicon dioxide host matrix. Each hybrid nanowire is made by core-shell structure used silicon as a core and gold as a shell. The hybrid nanowire-hyperbolic metamaterial is used as a top layer of a broadband absorber. The top layer is over on a planar silicon dioxide layer, which is backed by a nano-sized layer of gold as a perfect reflector for guaranteeing high absorbance. When electromagnetic waves in the range of 400–1600 nm wavelength are obliquely incident on the top hybrid nanowire-hyperbolic metamaterial surface, the absorption spectra of the designed absorber structure are analyzed for different incident angles, and radii of hybrid nanowire components or fill-factor of the hyperbolic metamaterial layer. The multiple absorption peaks, which are continuously generated from multiple longitudinal and transverse surface plasmon modes and are supported by the hybrid nanowires, are observed directly. The absorption feature can be also tuned by various operational conditions. The proposed structure is made by in-complex nano-fabricating techniques comparing with the another and it provides acceptable broadband absorptivity.
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Hybrid nanowires for phase-matching of third-harmonic generation in hyperbolic metamaterial
(2021-10-01)
Wicharn, Surawut
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Buranasiri, Prathan
We propose a phase-matching technique for third-harmonic generation, called hyperbolic phase matching, that possibly can be achieved by optimal designing and engineering dispersion of hybrid-nanowire hyperbolic metamaterial. We demonstrate phase-matched conditions for two different third-harmonic interacting configurations, which can be created at two optimal incident angles of the pump field. Moreover, each composed hybrid nanowire can enhance third-harmonic generation by using strong field confinement along the metal/dielectric interface due to plasmonic resonance. Finally, conversion efficiencies of transmitted and reflected third-harmonic pulses as a function of incident angle and input pulse intensity are examined by numerical integration of nonlinear birefringent coupled-mode equations. The numerical results validate the idea that, using a combination of phase-matched conditions and pump field confinement, we can achieve a dramatic enhancement of conversion efficiencies of third-harmonic generation.

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