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Size and Morphology Investigation of PZT Nanofibers for Energy Harvesting Applications using Digital Holography
(2025-01-01)
Plaipichit, S.
;
Wicharn, S.
;
Puttharugsa, C.
;
Bintachitt, P.
;
Aeimbhu, A.
Polyvinylidene fluoride fibers composed of piezoelectric lead zirconate titanate under different fabrication conditions were investigated using digital holography technique. Larger PZT content and larger feed rates results in larger diameters, and thicker fibers respectively.
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Size and Morphology Investigation of PZT Nanofibers for Energy Harvesting Applications using Digital Holography
(2025-01-01)
Plaipichit, S.
;
Wicharn, S.
;
Puttharugsa, C.
;
Bintachitt, P.
;
Aeimbhu, A.
Polyvinylidene fluoride fibers composed of piezoelectric lead zirconate titanate under different fabrication conditions were investigated using digital holography technique. Larger PZT content and larger feed rates results in larger diameters, and thicker fibers respectively.
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Backscattering and transmission Raman spectroscopy systems in the quantitative analysis concentration of acetone solutions
(2023-01-01)
Charoenrit, T. P.
;
Wicharn, S.
;
Puttharugsa, C.
;
Limnonthatul, P.
;
Sassuvun, W.
Raman spectroscopy is a set of techniques based on Raman scattering properties, widely applied to analyze the composition of various substances. The techniques consist of 1) backscattering, which collects Raman signals scattered from the surface of a sample; and 2) transmission, which collects Raman signals transmitted by the surface of a sample in the opposite direction of a light source (which triggers less fluorescence than backscattering). In this paper, we will measure the Raman spectrum of acetone solution by the transmission Raman spectroscopy and the backscattering Raman spectroscopy systems that we set up. Those accessories we use are a 532-nanometer diode laser with 100 milliwatt power as the light source, a focusing lens, an objective lens used for amplifying the Raman signals scattered from the sample, and a long-pass filter used to block light with a wavelength shorter than 532 nanometers. For the experimental samples, there are acetone solutions each prepared at 1M, 3M, 5M, 7M, 9M, 11M, and 13M. In the results of this experiment, we found that the intensity of Raman peaks for each Raman shift of acetone and the molar concentrations of acetone measured by both systems have a linear function in the backscattering Raman system and have a quadratic function in the transmissions Raman system because in backscattering system have noise by fluorescence effect more than in transmission system and it might be the effect of the Beer-Lambert law.
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Recursive transfer-matrix method for second-harmonic generation in a one-dimensional nonlinear photonic crystal at arbitrary incidence angle
(2021-01-28)
Threetanya, P.
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Puttharaksa, C.
;
Plaipichit, S.
;
Buranasiri, P.
;
Wicharn, S.
In this paper, we derive a recursive transfer-matrix method (RTMM) and use the method to analyse the problem of second-harmonic generation (SHG) in a one-dimensional nonlinear photonic crystal (1D-NPC) under oblique incidence of fundamental-frequency (FF) wave and nondepleted pump approximation. This method is very simple and useful for determining SHG conversion efficiency at various incident angles of FF wave and thicknesses of nonlinear layer. The RTMM calculation results show that a maximum SHG conversion efficiency can be produced by the strong local FF field confinement in 1D-NPC due to optimal incidence angle and nonlinear layer thickness.
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Virtual X-Ray Diffractometer using Acoustic Wave for Material Science Education
(2018-12-19)
Plaipichit, S.
;
Wicharn, S.
;
Puttharugsa, C.
;
Wanakamol, P.
;
Buranasiri, P.
In this research, virtual X-Ray Diffractometer (XRD) using acoustic wave for material science education has been proposed. Acoustic wave with frequency in ultrasonic range has been used to characterize acoustic crystal structures. The dimensions of model structure, which are in order of ultrasonic wavelength region, have been formed by three dimensional printer (3D printer) and cotton swab. The angle of ultrasonic source and detector have been swept to record reflected wave signal of each angle. The peak of each angle have been selected to calculate lattice spacing by Bragg's law and then compared with the implemented structure. The results show signal peaks of each diffracted angle. The experimental results showed that the lattice spacing values obtained from acoustic experiment were in good agreement with the measured values of the implemented structure. This virtual XRD system provide to be an efficient tool for understanding about crystal structure characterization.
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Backward Third-Harmonic Pulse Generation in a One-Dimensional PIM/NIM Structure
(2018-12-19)
Buranasiri, P.
;
Wicharn, S.
;
Yindeesuk, W.
In this work, a set of couple-mode equations for describing a backward third harmonic generation (BTHG) in a one-dimensional periodic structure of positive-index material (PIM) layers and third-order nonlinear negative-index material (NIM) layers was analysed using multiple-scale method. Due to the negative-index phase matching and band-edge field enhancement the intensities of backward third-harmonic pulsed generated from the PIM/NIM periodic structure is increased for 100 time of those generated from a single NIM medium.
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Cross-Polarized Wave Generation in a Nonlinear Hyperbolic Metamaterial
(2018-12-19)
Wicharn, S.
;
Buranasiri, P.
;
Plaipichit, S.
;
Reangchan, N.
A generation of cross-polarized wave (XPW) in nonlinear hyperbolic metamaterials (NHMM), which are composed of periodic arrangement of gold (Au) and barium difluoride (BaF <inf>2</inf> ) layers with subwavelength thickness for exhibiting anisotropy of permittivity and third-order nonlinearity, has been investigated numerically. This cubic nonlinear effect is described by degenerate four-wave mixing (DFWM) of three linearly polarized fields and one produced field, which has linear polarization in orthogonal direction. By managing the fill-factor value of the NHMM, the nearly phase-matched condition based on hyperbolic phase-matching (HPM) technique are achieved implicitly. We found that the conversion efficiencies of XPW generation as a function of incident angle at various pumping intensities are maximized at optimal incident angle.
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Intense terahertz-pulse generation by four-wave mixing process in induced gas plasma
(2015-01-01)
Wicharn, S.
;
Buranasiri, P.
In this article, we have numerically investigated an intense terahertz (THz) pulses generation in gaseous plasma based on the third-order nonlinear effect, four-wave mixing rectification (FWMR). We have proposed that the fundamental fields and second-harmonic field of ultra-short pulse lasers are combined and focused into a very small gas chamber to induce a gaseous plasma, which intense THz pulse is produced. To understand the THz generation process, the first-order multiple-scale perturbation method (MSPM) has been utilized to derive a set of nonlinear coupled-mode equations for interacting fields such as two fundamental fields, a second-harmonic field, and a THz field. Then, we have simulate the intense THz-pulse generation by using split step-beam propagation method (SS-BPM) and calculated output THz intensities. Finally, the output THz intensities generated from induced air, nitrogen, and argon plasma have been compared.
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Nonlinear frequency conversion effect in a one-dimensional graphene-based photonic crystal
(2015-01-01)
Wicharn, S.
;
Buranasiri, P.
In this research, the nonlinear frequency conversion effect based on four-wave mixing (FWM) principle in a onedimensional graphene-based photonics crystal (1D-GPC) has been investigated numerically. The 1D-GPC structure is composed of two periodically alternating material layers, which are graphene-silicon dioxide bilayer system and silicon membrane. Since, the third-order nonlinear susceptibility χ<sup>(3)</sup> of bilayer system is hundred time higher than pure silicon dioxide layer, so the enhancement of FWM response can be achieved inside the structure with optimizing photon energy being much higher than a chemical potential level (μ) of graphene sheet. In addition, the conversion efficiencies of 1DGPC structure are compared with chalcogenide based photonic structure for showing that 1D-GPC structure can enhance nonlinear effect by a factor of 100 above the chalcogenide based structure with the same structure length.
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Third-harmonic generation enhancement in polymer-dispersed liquid crystal grating
(2014-01-01)
Wicharn, S.
;
Buranasiri, P.
In this paper, the enhancement of third-harmonic generation in one-dimensional periodic grating structure with lowindex contrast, which is produced by holographic illuminated liquid crystal droplets and called polymer-dispersed liquid crystal grating, with near-infrared pumping has been demonstrated. The observed enhancement process is theoretically explained and modeled with a multi-scale perturbation analysis and split-step Fourier transform technique, respectively. We show that the third-harmonic generation has been enhanced by setting the fundamental frequency wavelength to the long-wavelength band-edge of the first photonic band-gap of this periodic structure and satisfying band-edge phasematched condition. The numerical results show that a dramatic enhancement of the third-harmonic field is observed near the long-wavelength band-edge of the second photonic band-gap. Furthermore, the conversion efficiency of thirdharmonic field of forward-propagating direction is more than of backward-propagating direction by a factor of 600.

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