A5017798388- Laser-Plasma Interactions and Diagnostics
- Advancements in Solid Oxide Fuel Cells
- Electronic and Structural Properties of Oxides
- Laser-Matter Interactions and Applications
- Gyrotron and Vacuum Electronics Research
- Laser-induced spectroscopy and plasma
- Particle Accelerators and Free-Electron Lasers
- Terahertz technology and applications
- Laser Design and Applications
- Advanced X-ray Imaging Techniques
- Magnetic and transport properties of perovskites and related materials
- Particle accelerators and beam dynamics
- Photonic and Optical Devices
- Nuclear Physics and Applications
- Atomic and Molecular Physics
- Catalytic Processes in Materials Science
- Plasma Diagnostics and Applications
- Ion-surface interactions and analysis
- Microwave Engineering and Waveguides
- Optical Coatings and Gratings
- Ammonia Synthesis and Nitrogen Reduction
- Advanced Electron Microscopy Techniques and Applications
- Electrocatalysts for Energy Conversion
- Spectroscopy and Laser Applications
- Photonic Crystals and Applications
Agency for Defense Development
2023-2024
Jeonbuk National University
2013-2024
Korea Atomic Energy Research Institute
2015-2024
Wonkwang University
2024
Gwangju Institute of Science and Technology
2023
Korea University of Science and Technology
2015-2022
Budker Institute of Nuclear Physics
2020
Lawrence Livermore National Laboratory
2020
Chonbuk National University Hospital
2008-2016
Catholic University of Daegu
2014
We report a new synthetic method for the preparation of high-performance polyaniline, implementing concept self-stabilized dispersion polymerization. In contrast with conventional homogeneous or polymerization methods that use an aqueous medium containing aniline, acid, and oxidant, our is performed in heterogeneous biphasic system organic without any stabilizers. Here, monomers growing polymer chains act as stabilizers, resulting excellent phase inside reaction medium. Polymerization based...
Relativistic, nonlinear Thomson scattering by an electron of intense laser field has been investigated computer simulation. Under a with pulse duration 20-fs full width at half maximum and intensity 10(20) W/cm(2), the motion is highly relativistic generates ultrashort radiation 2 as photon energies from 100 to 600 eV. An interesting modulated structure spectrum observed analyzed. A produced zigzag under linearly polarized better characteristics than helical circularly in terms angular...
We investigate transmission characteristics and sheet conductivity of mono- to multi-layer graphene deposited on quartz in the terahertz (THz) frequency region. The free carrier absorption Fabry-Perot interference between layers give rise nonlinear decrease THz from 76.7% 27% for 12-layer graphene. These phenomena are well explained with a modified theoretical model based Drude conductivity. optical graphene, made by layer-by-layer random stacking high-quality mono-layer at 1 exhibits two...
Milled MgH2, NaAlH4, MgH2–10NaAlH4, MgH2–30NaAlH4, MgH2–50NaAlH4, and MgH2–2Ni-10NaAlH4 samples were prepared by milling in hydrogen atmosphere (reactive mechanical milling, RMM). Decomposition temperatures of milled MgH2–30NaAlH4 examined a Sieverts-type hydrogen-absorption release apparatus, which the pressures kept constant during absorption or release. As content NaAlH4 sample increased, temperature at highest peak ratio increase Hr to T, dHr/dT, versus T curve decreased. The higher is...
Abstract In this paper, we propose a terahertz (THz) guided-mode resonance (GMR) notch filter made of monolithic polyethylene terephthalate (PET) film, which has monolayer grating structure. The proposed configuration shows both polarization-dependent and polarization-independent characteristics for the incident THz wave depending on rotation angle second film. When is 0°, filtering strength (transmittance) at frequency changes from 0.4 (0.996) to 99.0% (0.010) according polarization....
Abstract A power conversion efficiency (PCE) exceeding 25% is achievable using perovskite solar cells (PSCs), with compositional engineering as the most effective strategy for high‐efficiency PSCs. However, understanding of structural properties, charge‐carrier dynamics, and photoelectric crucial cell performance, still remains insufficient to establish a correlation device performance improving PCE stability This study uncovers links between disorder, properties mixed‐perovskite (FAPbI 3 )...
The condition for the coherent addition of relativistic nonlinear Thomson scattered (RNTS) radiations from a group electrons is derived. Numerical calculations show that under such condition, all characteristics RNTS radiation by single electron are maintained, leading to generation intense attosecond x rays. Such an ray produced in specific direction with very narrow angular divergence. An x-ray ∼1016W∕cm2 pulse width 7.7 as expected oblique irradiation 20 fs linearly polarized laser...
We realized a variable-period permanent-magnet helical undulator with high ($\ensuremath{\sim}1\text{ }\text{ }\mathrm{T}$) field amplitude, which is almost constant over periods of 23--26 mm. Each period has four modular sections iron poles and permanent magnets embedded in nonmagnetic disks holes along the axis. Modular plates undergo longitudinal repulsive force from magnetic pressure spring coils between plates. The can thus be controlled by mechanically changing end plate position. This...
We propose an all-dielectric single-layer guided-mode resonance filter (GMRF) operating in the high-frequency terahertz (THz) region. For fabrication of thin gratings to achieve strong region, refractive index and absorption must be small, while tensile strength high. Cyclic olefin copolymer (COC) films have a lower than polyethylene terephthalate (PET) higher yield polytetrafluoroethylene (PTFE) films. Therefore, COC film was found suitable fabricate GMRF THz fabricated COC-based GMRFs with...
The harmonics of the scattering a femtosecond intense laser pulse by an electron has been numerically investigated. harmonic spectrum shows interesting red shifts and parasitic lines in blue sides lines. shift is found to be caused dilation oscillation experienced due its relativistic drift motion along direction driving propagation come from variation intensity. angular distribution each higher line double peak patterns forward direction. backward own distinct pattern: line-shaped nodes...
The radiation of a relativistic electron interacting with co-propagating tightly focused high-power laser is investigated. High-order fields (HOFs) existing in tight focus (a few micrometers or so) affect the dynamics electrons rather significantly so as to enhance intensity by several orders magnitude. In case interaction geometry, second-order field plays an important role enhancement. It demonstrated that when HOFs are included, efficiency increased factor up 100 000 for w0 = 2 and 5 μm,...