A5100686007- Adaptive optics and wavefront sensing
- Optical Systems and Laser Technology
- Graphene research and applications
- GaN-based semiconductor devices and materials
- 2D Materials and Applications
- Semiconductor Quantum Structures and Devices
- Astronomy and Astrophysical Research
- MXene and MAX Phase Materials
- Radiation Detection and Scintillator Technologies
- Supercapacitor Materials and Fabrication
- Laser-induced spectroscopy and plasma
- Optical Coatings and Gratings
- Gas Sensing Nanomaterials and Sensors
- Mass Spectrometry Techniques and Applications
- Graphene and Nanomaterials Applications
- Advancements in Semiconductor Devices and Circuit Design
- Quantum and electron transport phenomena
- Ga2O3 and related materials
- Luminescence Properties of Advanced Materials
- Radio Astronomy Observations and Technology
- Force Microscopy Techniques and Applications
- Advanced Sensor and Energy Harvesting Materials
- Dielectric materials and actuators
- Polymer crystallization and properties
- Thermal properties of materials
Kyung Hee University
2024
Seoul National University
2020-2023
Green Technology Center
2022-2023
Mokpo National University
2021-2023
Chungbuk National University
2020
Samsung (Japan)
2015
Friedrich-Alexander-Universität Erlangen-Nürnberg
2010
Pohang University of Science and Technology
2008
Washington University in St. Louis
2008
Hanyang University
2008
Highly dispersive molybdenum disulfide nanoflakes (MoS2 NFs), without any phase transition during the exfoliation process, are desirable for full utilization of their semiconductor properties in practical applications. Here, we demonstrate an innovate approach fabricating MoS2 NFs by using hydrazine-assisted ball milling via synergetic effect chemical intercalation and mechanical exfoliation. The obtained have a lateral size 600-800 nm, thickness less than 3 high crystallinity 2H...
This study presents a method to measure the contact angles of oils on substrate in water. Diiodomethane and perfluorodecalin were used as model oils. Self-assembled monolayers (SAMs) prepared by adjusting mole ratio CH3- OH-terminated alkanethiols. The two water increased with increasing hydrophilicity SAMs, results are contrasted these surfaces air. In addition, showed higher than diiodomethane same surface. On poly(N-isopropylacrylamide) (PNiPAAM) monolayer surface, decreased sharply at...
A solid state combinatorial chemistry approach has been adopted for the synthesis of Eu2+ and Ce3+-doped compositions comprising AE-Sc-Si-O-N (AE = Mg, Ca, Sr, Ba) in search a novel phosphor application converted white light emitting diodes (pc-WLEDs). An extensive powder X-ray diffraction analysis reveals discovery Mg-Sc-Si-O-N system. The discovered was sense that XRD pattern do not matches with any available crystallographic information data base (ICDD or ICSD) no study carried out on...
Abstract In a ΛCDM universe, most galaxies evolve by mergers and accretions, leaving faint and/or diffuse structures, such as tidal streams stellar halos. Although these structures are good indicator of galaxies’ recent mass assembly history, they have the disadvantage being difficult to observe due their low surface brightness (LSB). To recover LSB features minimizing photometric uncertainties introduced optical system, we developed new optimized telescope named K-DRIFT pathfinder, adopting...
The prototype of KASI-Deep Rolling Imaging Fast-optics Telescope (K-DRIFT) pathfinder is a 300 mm confocal off-axis freeform three-mirror system that has been developed for the detection extended low surface brightness (LSB; below μV = 28 mag arcsec<sup>-2)</sup> structures. Until now, it still very difficult to observe LSB features due systematic errors introduced by natural and instrumental effects. To overcome these, we apply telescope design theory removed linear astigmatism, each mirror...
A TTL (through-the-lens) alignment system using the holographic phase conjugation in photopolymer films for application to ArF step-and-scan exposure was designed, and signals were obtained. The optical setup is similar DFWM (degenerate four-wave mixing). recording materials HRF 150 of Du Pont corporation, wavelength 476 nm argon ion laser with 400 mW output power. diffraction efficiencies film typically around 50%. Fine patterns as small 1 micron imaged successfully by conjugate waves...
In this study, we demonstrate a carbon-based fabric Joule heater with and without graphene oxide (GO) thin coating. The electrothermal performance of the carbon used in was obtained using an infrared camera by conducting electrical measurements. outer GO could control efficiency heating rate. research work, films, report adaptive thermal covering temperatures ranging 30 to 50 °C (near infrared). This materials can be potential nano-materials for various functional applications. Moreover,...
Abstract We studied the optical response and visibility of inside graphene layer in hBN/graphene/hBN on SiO 2 /Si substrate, revealing why is invisible microscope image. The observed behavior for stack systematically supported by calculation analysis, which investigated reflectance contrast spectra based matrix method. substrate effect allows us to maximize hBN micrograph, suggesting a simple approach make visible.
We have developed the KASI-Deep Rolling Imaging Fast Telescope (K-DRIFT), adopting a 300 mm aperture off-axis freeform three-mirror design to detect faint and diffuse low-surface-brightness structures. By conducting on-sky test observations performing series of simulations analyze performance K-DRIFT, we confirmed three main error sources causing optical degradation. The imaging K-DRIFT has successfully improved by correcting low-to-mid spatial frequency wavefront errors based on analysis...
We are developing the KASI-Deep Rolling Imaging Fast Telescope Generation 1 (K-DRIFT G1) based on on-site performance assessment of K-DRIFT pathfinder. The telescope is a confocal off-axis freeform three-mirror system designed for detection extremely low surface brightness structures in sky. optical specifications G1 as follows: entrance pupil diameter 300 mm, focal ratio 3.5, field view 4.43° × 4.43°, and image area 81.2 mm with 10 μm pixels. performed sensitivity analysis tolerance...
We fabricated three freeform mirrors for the KASI-Deep Rolling Imaging Fast Telescope pathfinder, which is a confocal off-axis three-mirror system with 300 mm entrance pupil diameter. During fabrication process, we light-weighted primary mirror, reducing its weight by 52%. Front surfaces of these were formed series production including grinding, polishing, forming, and finishing. Measuring surface profile has been performed using Coordinate Machines (CMMs) grinding process an interferometer...
Abstract not Available.