Jun-Kyu Kang
Samsung
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by Jun-Kyu Kang.
Journal of The Korean Magnetics Society | 2011
Jihoon Hwang; D. H. Kim; Eunsook Lee; Jun-Kyu Kang; Woochur Kim; Cheulgon Kim; Sun-Hee Han; Sung-Ok Hong; Byungjae Park; Ju-Yeop Kim
The electronic structure of ferrimagnetic spinel oxide of has been investigated by employing soft x-ray absorption spectroscopy (XAS) and soft x-ray magnetic circular dichroism (XMCD). The Fe 2p and V 2p XAS spectra show that the valence states of Fe and V ions are mixed-valent states and states, respectively. In Fe 2p XMCD spectra, finite XMCD signals are observed for divalent states only, but not for states. This finding indicates that the magnetic moments of ions are ordered ferromagnetically but that those of ions are cancelled, implying that ions play an important role in determining magnetic properties of .
Journal of The Korean Magnetics Society | 2016
D. H. Kim; Eunsook Lee; Hyunwoo Kim; Seungho Seong; Jun-Kyu Kang; Seung-Mo Yang; Hae-Soo Park; JinPyo Hong
We have investigated the electronic structures of intermetallic multilayer (ML) films of [Co(2A)/Pd(xA)] (x: the thickness of the Pd sublayer; x = 1 A, 3 A, 5 A, 7 A, 9 A) by employing soft X-ray absorption spectroscopy (XAS) and soft X-ray magnetic circular dichroism (XMCD). Both Co 2p XAS and XMCD spectra are found to be similar to one another, as well as to those of Co metal, providing evidence for the metallic bonding of Co ions in [Co/Pd] ML films. By analyzing the measured Co 2p XMCD spectra, we have determined the orbital magnetic moments and the spin magnetic moments of Co ions in [Co(2A)/Pd(xA)] ML films. Based on this analysis, we have found that the orbital magnetic moments are enhanced greatly when x increases from 1 A to 3 A, and then do not change much for x ≥ 3 A. This finding suggests that the interface spin-orbit coupling plays an important role in determining the perpendicular magnetic anisotropy in [Co/Pd] ML films.
Journal of The Korean Magnetics Society | 2016
Seungho Seong; Eunsook Lee; Hyunwoo Kim; D. H. Kim; Jun-Kyu Kang; M. Venkatesan; J.M.D. Coey
By employing photoemission spectroscopy (PES) and soft X-ray absorption spectroscopy (XAS), the electronic structure of the candidate half-metallic antiferromagnet of Mn3Ga Heusler compound has been investigated. We have studied two ball-milled Mn3Ga powder samples, one after annealing and the other without annealing, respectively. Based on the Mn 2p XAS study, we have found that Mn ions are nearly divalent in Mn3Ga and that the Mn ions having the locally octahedral symmetry and those having the locally tetrahedral symmetry are both present in Mn3Ga. We have found relatively good agreement between the measured valence-band PES spectrum of Mn3Ga and the calculated density of states, which is in agreement with the half-metallic electronic structure of Mn3Ga.
Journal of The Korean Magnetics Society | 2015
Hyun Woo Kim; Eunsook Lee; D. H. Kim; Seungho Seong; Jun-Kyu Kang; Surk-Sik Moon; Yuju Shin
The electronic structures of the potential candidate semiconductor nanoparticles for dye-sensitized solar cell (DSSC), such as and , have been investigated by employing X-ray photoemission spectroscopy (XPS). The measured X-ray diffraction patterns show that and samples have the single-phase ilmenite-type structure and the inverse spinel structure, respectively. The measured Zn 2p and Sn 3d core-level XPS spectra reveal that the valence states of Zn and Sn ions are divalent (Zn 2+) and tetravalent (Sn 4+), respectively, in both and . On the other hand, the shallow core-level measurements show that the binding energies of Sn 4d and Zn 3d core levels in are lower than those in . This work provides the information on the valence states of Zn and Sn ions and their chemical bonding in and .
Journal of The Korean Magnetics Society | 2012
Eunsook Lee; D. H. Kim; Jihoon Hwang; Kiho Lee; Jun-Kyu Kang
By employing soft x-ray absorption spectroscopy (XAS) and soft x-ray magnetic circular dichroism (XMCD), the electronic structures of molecule-based nano bioparticles, such as Helicobacter pylori ferritin (H. pylori ferritin), Heme, -type Prussian Blue (M
Archive | 2001
Dong-In Ha; Wan-Jin Choi; Dong-Hwan Kim; Jun-Kyu Kang
Archive | 2002
Jun-Kyu Kang; Dong-In Ha; Wan-Jin Choi; Jung-Ho Park; Dong-Hwan Kim
Archive | 2006
Hae-Dong Yeon; Young-Hak Kim; Jae-Hwan Chang; Jae-Yong Lee; Min-Cheol Park; Ji-Yun Seol; Tae-Gon Kim; Jun-Kyu Kang; In-Hyoung Kim; Yun-Sang Park; Bong-Gee Song
Archive | 2008
Jun-Kyu Kang; In-Tae Kang; Jeong-gil Lee; Bo-Rham Lee; Sang-Min Bae
Archive | 2008
Bo-Rham Lee; Jong-Hun Rhee; Min-goo Kim; In-Tae Kang; Jun-Kyu Kang