A5084735012- Laser-Matter Interactions and Applications
- Laser-Plasma Interactions and Diagnostics
- Laser-induced spectroscopy and plasma
- Advanced Chemical Physics Studies
- Gyrotron and Vacuum Electronics Research
- Laser Design and Applications
- Catalysis and Oxidation Reactions
- Spectroscopy and Quantum Chemical Studies
- Mass Spectrometry Techniques and Applications
- Particle Accelerators and Free-Electron Lasers
- Enzyme Structure and Function
- Spectroscopy and Laser Applications
- Advanced Fiber Laser Technologies
- Radioactive element chemistry and processing
- Protein Structure and Dynamics
- Metal-Organic Frameworks: Synthesis and Applications
- Innovative Microfluidic and Catalytic Techniques Innovation
- Superconducting and THz Device Technology
- Optical Network Technologies
- Advanced Sensor Technologies Research
- Ophthalmology and Eye Disorders
- Ion-surface interactions and analysis
- Mesoporous Materials and Catalysis
- Laser Material Processing Techniques
- Covalent Organic Framework Applications
Korea Advanced Institute of Science and Technology
2000-2025
Institute for Basic Science
2023-2025
Korean Academy of Science and Technology
2017
Korea Atomic Energy Research Institute
2002-2011
Kongju National University
2011
Hannam University
2011
Chungnam National University
2009
University of California System
2008
University of Michigan
1991
Abstract Crystalline systems consisting of small-molecule building blocks have emerged as promising materials with diverse applications. It is great importance to characterize not only their static structures but also the conversion in response external stimuli. Femtosecond time-resolved crystallography has potential probe real-time dynamics structural transitions, but, thus far, this been realized for chemical reactions non-biological crystals. In study, we applied serial femtosecond...
Abstract Molecular ions are ubiquitous and play pivotal roles 1–3 in many reactions, particularly the context of atmospheric interstellar chemistry 4–6 . However, their structures conformational transitions 7,8 , gas phase, less explored than those neutral molecules owing to experimental difficulties. A case point is halonium 9–11 whose highly reactive nature ring strain make them short-lived intermediates that readily attacked even by weak nucleophiles thus challenging isolate or capture...
Abstract Bond rotation is an important phenomenon governing the fate of reactions. In particular, heterogeneously substituted ethane derivatives provide distinct structural conformations around bond, empowering them as ideal systems for studying along carbon-containing single bonds. However, dynamics ultrafast single-bond rotation, especially C–C• bonds, have remained elusive tracking detailed changes in parameters during rotational isomerization challenging with conventional spectroscopic...
Recently sensitive micro-magnetic sensors are strongly required in various technologies such as BT and IT. This paper gives the comprehensive analysis of Asymmetric Giant MagnetoImpedance (AGMI) sensor's performance with negative feedback. Asymmetrical behavior GMI is for linear magnetic field sensitivity linearity most important parameters practical application to sensors, this has been realized by annealing amorphous ribbon. A novel AGMI sensor was developed carefully studied without...
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...
Proton beams generated from thin aluminum and Mylar foil targets that are irradiated by a $30\phantom{\rule{0.3em}{0ex}}\mathrm{fs}$ Ti:sapphire laser pulse with an intensity of $2.2\ifmmode\times\else\texttimes\fi{}{10}^{18}\phantom{\rule{0.3em}{0ex}}\mathrm{W}∕{\mathrm{cm}}^{2}$ were investigated. Protons the observed to have energy higher factor 2 in number order magnitude as compared those targets. The maximum proton...
Time-resolved x-ray liquidography (TRXL) is a potent method for investigating the structural dynamics of chemical and biological reactions in liquid phase. It has enabled extraction detailed aspects various dynamic processes, molecular structures intermediates, kinetics across wide range systems, from small molecules to proteins nanoparticles. Proper data analysis key extracting information studied system encrypted TRXL data. In typical data, signals solute scattering, solvent solute-solvent...
An experimental observation has been made by using aluminum-coated Mylar foils, which strongly supports that in the case of plastic target, energetic part proton beam originates from front-side target. When a 30 fs laser pulse with an intensity 1.6×1019 W/cm2 was irradiated on 12.5-μm-thick side foil, maximum energy reduced factor 5.5 as compared to 3.3 MeV observed single layer foil. With help two-dimensional particle-in-cell simulation, these observations can be interpreted In 6-μm-thick...
[Ce(III)Cl6]3–, with its earth-abundant metal element, is a promising photocatalyst facilitating carbon–halogen bond activation. Still, the structure of reaction intermediate has yet to be explored. Here, we applied time-resolved X-ray liquidography (TRXL), which allows for direct observation structural details intermediates, investigate photocatalytic [Ce(III)Cl6]3–. Structural analysis TRXL data revealed that excited state [Ce(III)Cl6]3– Ce–Cl bonds are shorter than those ground and...
The effect of a laser prepulse on the generation proton beams is compared between plastic and metal targets by irradiating 30fs, 2.4×1018W∕cm2 Ti:sapphire pulse. Proton energies generated from both target materials increase as pulse duration decreases. However, it was found that there are distinct differences with respect to materials. In case aluminum targets, thickness decreases, energy gets higher, which well described an isothermal expansion model. in Mylar® no such dependence could be...
Iodoform (CHI
Novel crystalline materials consisting of organic, inorganic or organometallic building blocks have emerged as promising with wide applications [1-5]. Of great importance is to characterize not only the static structures those grown in single crystals but also conversion their response external stimuli [6, 7]. Femtosecond time-resolved crystallography has potential probe real-time dynamics such structural conversions yet been realized for chemical reactions made small-molecule blocks. Here,...
Recent progress of terahertz (THz) technology opens new applications security inspection and biomedical developments. In some applications, the power THz radiation is crucial for realization in field. We have developed a laboratory-size high free electron laser (FEL) its application to imaging, spectroscopy, material study. found that table-top FEL having more than 1-W could be source real-time imaging system inspection. This paper introduces design review high-power potential based on our...
We have designed a table-top terahertz (THz) free electron laser (FEL). The main issue of the FEL design is to decrease radiation losses at resonator except outcoupling ratio. Also reducing number undulator periods and total length important increase conversion efficiency reduce its size. consists magnetron-based microtron having an energy ~5 MeV, strong electromagnetic helical period ~25 mm, cylindrical waveguide-mode optical resonator. diameter approximately 50 cm macropulse current more...