• Title/Summary/Keyword: 3D PD

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Electronic Structures of Co-Pd Alloy Films Using Synchrotron Radiation Photoemission Spectroscopy (방사광 광전자 분광법을 이용한 Co-Pd 합금박막의 전자구조 연구)

  • 강정수;권세균;하양장;민병일;조용필;이창섭;정인범;구양모;김건호
    • Journal of the Korean Magnetics Society
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    • v.6 no.6
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    • pp.405-410
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    • 1996
  • Valence band photoemission spectroscopy (PES) measurements have been performed for $Co_{x}Pd_{100-x}$ alloy films using synchrotron radiation (x = 0, 25, 40, 65). Then the partial spectral weight distributions (PSW's) of Co 3d and Pd 4d electrons have been determined. The Co 3d PSW's exhibit some structures which are quite different from those of the Co film for x < 25 %, whereas they become very similar to those of the Co film for x > 40 %. For x < 25 %, the peak near the Fermi level ($E_F$) and a shoulder around 2 eV binding energy in the Co 3d PSW reflect large hybridization between Pd 4d and Co 3d electrons, suggesting that the hybridization might play an inportant role in determining perpendicualr magnetic anisotropy. The Pd 4d PSW's in Co-Pd alloy films are found to have larger FWHM's (full widths at half maximum), larger binding energies of the main peaks, and larger spectral intensities at $E_F$ than the PES spectrum of the Pd film. The FWHM of the Pd 4d PSW increases with decreasing Pd concentration, which are considered to reflect the disordering effect in the alloy formation or the change in the Pd 4d electronic structure due to hybridization between Co 3d and Pd 4d electrons.

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Electronic Structure and Magnetism of (3d, 4d)-Pd Alloyed c(2×2) Monolayers (3d 및 4d 전이금속과 Pd가 c(2×2) 합금을 이룬 단층의 자성에 대한 제일원리 연구)

  • Kim, Dong-Chul;Choi, Chang-Sik
    • Journal of the Korean Magnetics Society
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    • v.20 no.3
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    • pp.83-88
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    • 2010
  • We investigated the electronic structure and magnetism of the (3d, 4d)-Pd alloyed c($2{\times}2$) monolayer systems, by use of the FLAPW band method. For comparison, pure 3d- and 4d-transition metal monolayers are also considered. We found that the antiferromagnetic configuration of pure V monolayers is sustained in the V-Pd alloy system, while the Ti-Pd alloy system is changed to antiferromagnetic configuration from the ferromagnetic state in pure Ti monolayer. The 4d TM (Mo, Ru, Rh)-Pd monolayers are found to be stable in ferromagnetic configurations. The magnetic moments of Ru and Rh atoms in Ru-Pd and Rh-Pd systems are almost same with those of pure Ru and Rh monolayers, while the magnetic moment of Mo atom is increased to $2.98\;{\mu}_B$ in Mo-Pd alloyed system from the value of Mo monolayer, $0.02\;{\mu}_B$.

Study of the formation of Pd-silicide with x-ray photoelectron spectroscopy (광전자분광법을 이용한 Pd-실리사이드의 형성 연구)

  • 조은진;최일상;이한길;황찬용
    • Journal of the Korean Vacuum Society
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    • v.6 no.2
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    • pp.165-171
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    • 1997
  • If the thickness of Pd deposited is larger than 9$\AA$, its phase is $Pd_3Si$. This phase is followed by pure Pd phase with further deposition of Pd. Also, when the thickness of Pd deposited on top of Si(111) is larger than 1$\AA$, the phase of Pd-silicide formed is found to be Pd2Si. The full width at half maximum of Pd 3d core-levels increases with decreasing of Pd film thickness at low coverages ($\leq0.5\AA$). This is due to the formation of additional phase of Pd silicide, i.e. PdSi, in addition to $Pd_2Si$.

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New Packaging and Characteristics of PIN PD for CWDM Transmission (저밀도 파장분할 다중화용 PIN PD 제작 및 특성)

  • Kang, Jae-Kwang;Chang, Jin-Heyon
    • Journal of the Microelectronics and Packaging Society
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    • v.12 no.4 s.37
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    • pp.323-330
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    • 2005
  • We fabricate PIN PD (Positive Intrinsic Negative Photo-Diode) for CWDM optical repeater and optical transmission system, and analyze theoretically the characteristics to verify the capability of device fabricated. Furthermore, we integrate CWDM filter into PD package to enhance the cost and the performance when compared to the conventional system, in which CWDM filter and PD package are linked by optical fusion splicing. The integrated CWDM PD is fabricated by three steps as follows: CWDM filter design, PD packaging, and product assembly and test. The results of measurement for PD fabricated reveal 0.5 dB bandwidth of 17 nm, isolation over 60 dB at transmission port and over 20 dB at reflection port. Also, the IMD3 for wireless communication is over 63 dBc, and the responsivity of PD presents over 0.9 A/W for 20 samples of the total 23 PD. The total insertion loss reduces about 0.4${\~}$0.7 dB due to the integrated assembly of CWDM and PD.

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Valence Band Photoemission Study of Co/Pd Multilayer (광전자분광법을 이용한 Co/Pd 다층박막의 전자구조연구)

  • Kang, J.-S.;Kim, S.K.;Jeong, J.I.;Hong, J.H.;Lee, Y.P.;Shin, H.J.;Olson, C.G.
    • Journal of the Korean Magnetics Society
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    • v.3 no.1
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    • pp.48-55
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    • 1993
  • We report the photoemission (PES) studies for the Co/Pd multilayter. The Co 3d PES spectrum of Co/Pd exhibits two interesting features, one near the Fermi energy, $E_{F}$, and another at ~2.5 eV below $E_{F}$. The Co 3d peak near $E_{F}$ of Co/Pd is much narrower than that of the bulk Co, consistent with the enhanced Co magnetic moment in Co/Pd compared to that in the bulk Co. The Co 3d feature at ~-2.5 eV resembles the Pd valence band structures, which suggests a substantial hybridization between the Co and Pd sublayers. The Co 3d PES spectrum of Co/Pd is compared with the existing band structures, obtained using the local spin density functional calculations. A reasonable agreement is found concerning the bandwidth of the occupied part of the Co 3d band, whereas a narrow Co 3d peak near $E_{F}$ seems not to be described by the band structure calculations.

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Evaluation of Visual Responses in Viewing a 3D Image (3D 영상 시청 시 시각반응의 평가)

  • Lee, Mu-Hyuk;Son, Jeong-Sik;Kim, Jaedo;Yu, Dong-Sik
    • Journal of Korean Ophthalmic Optics Society
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    • v.17 no.2
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    • pp.165-170
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    • 2012
  • Purpose: The aim of this study was to measure and evaluate changes of visual responses in viewing a 2D and 3D (three-dimensional) image. Methods: The subjects were 44 college students aged 19 to 25 years with normal binocular vision. The visual responses measured were CA/C (convergence accommodation/convergence) ratio, convergence-induced PD(interpupillary distance), accommodative responses, perceived distance in viewing a 3D image. Results: Convergence and accommodative responses in viewing the 3D image were significantly larger (p<0.05) than in 2D. A moderate positive correction was found between CA/C ratio and accommodative response (r = 0.477, p = 0.001). It was indicated that smaller PD had larger depth perception. Convergence in viewing the 3D image was significantly larger (p<0.05) than that at cognitive distance. Conclusions: The visual fatigue may be more intense in larger CA/C ratio and smaller PD when viewing 3D images.

First-Principles Theoretical Study of the Surface Structure of O/Pd(100)-p($2{\times}2$) and the Effect of H Impurities (O/Pd(100)-p($2{\times}2$) 표면구조 및 수소흡착 효과의 제일원리 이론계산 연구)

  • Jung Sung-Chul;Kang Myung-Ho
    • Journal of the Korean Vacuum Society
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    • v.15 no.4
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    • pp.360-366
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    • 2006
  • We have performed density functional theory calculations for the surface structure of O/Pd(100)-p($2{\times}2$), formed by the adsorption of oxygen atoms of 0.25 ML. The oxygen atoms adsorb preferentially at the fourfold hollow site, and the calculated O-Pd bond length is $2,15{\AA}$, The first interlayer spacing ($d_{12}$) of Pd(100) expands by +0.8% due to the oxygen adsorption, which differs from the experimental value of +3.6% reported by a previous LEED study. Assuming that the LEED sample was possibly contaminated by hydrogen atoms, we also examined the effect of hydrogen impurities on the surface structure. Hydrogen atoms adsorbed on O/Pd(100)-p($2{\times}2$) are found to result in large expansions of $d_{12}$ of Pd(100). Our analysis estimates the amount of hydrogen atoms remaining on the LEED sample as -0.3 ML.

A Study of PD System Effectiveness based on R&D Network Analysis (R&D 네트워크 분석을 통한 PD 제도 효과 연구)

  • Park, Mi-Yeon;Lee, Sangheon;Shen, Hongme;Leem, Choon Seong;Kim, Wooju
    • The Journal of Society for e-Business Studies
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    • v.20 no.3
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    • pp.29-46
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    • 2015
  • Examined how it varied the knowledge network of the country along with R&D changes in planning policy for the research and development of government. Therefore, in this study, chronological Analysis analyzed separately the network between each entity of participate in the industry fusion source technology development business of industry trade and Energy. Planning policy of industrial fusion source technology development business, to change the starting point before and after 2012, before 2012 from selected planning issues at the center "planning committee" and in 2012 'PD' changes to a system for planning issues around. First of all, an attempt to analyze the R&D network based on the "planning committee" current situation of 2009~2011, from 2012 to analyze the variation of the R&D network with the introduction of the 'PD' system after it was analyzed by dividing the time in the current state of up to 2013. The results of the analysis, since the PD system was introduced, such as self-relationship (the form of planning user to run directly challenges the person was planning to challenge participants)is greatly improved, I was able to grasp the effect became clear. The more the self-relation, and the budding scholars considering that there is inequality of the planning, the introduction of the PD scheme, it can be seen to have resulted in a positive effect. These studies, quantitatively analyzed to improve the results to the effects associated with changes in the planning policy of the government, I think that there is a meaning in terms of presenting the future direction of R&D policy.

ELECTRONIC STRUCTURES AND MAGNETIC PROPERTIES OF HEUSLER COMPOUNDS: XMnSb (X=Ni, Pd, and Pt)

  • Youn, S.J.;Min, B.I.;Jang, Y.R.
    • Journal of the Korean Magnetics Society
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    • v.5 no.5
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    • pp.749-752
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    • 1995
  • Electronic structures of the Heusler compounds, XMnSb (X=Ni, Pd, and Pt) are investigated systematically by using the linearized muffiu-tin orbital (LMTO) band method. LMTO band calculations yield that, by including the spinorbit interactions, the NiMnSb and PtMnSb are half-metallic, while PdMnSb is normal metallic at the experimental lattice constant. The effect of the spin-orbit interaction is substantial in PtMnSb, in contrast to NiMnSb and PdMnSb. The calculated X d and Mn 3d angular momentum projected local density of states's reveal that the hybridization between the Mn 3d X d states increases from X = Pt to Pd and Ni.

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In Watching 3D Stereoscopic Display Using the Binocular Disparity, the Effect of Pupillary Distance of Adults and Children on the Perception of 3D Image (양안시차를 이용한 3D 입체영상 장치의 시청에 있어 성인 및 아동의 동공간거리가 미치는 영향)

  • Kang, Seok Hyon;Hong, HyungKi
    • Journal of Korean Ophthalmic Optics Society
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    • v.16 no.3
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    • pp.299-305
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    • 2011
  • Purpose: In watching 3D stereoscopic display using the binocular disparity, effect of difference of the pupillary distance between the adults and children on the perception of depth were investigated. Methods: The average PD of children was determined from the PD measurements of children of the elementary school of 2nd and 3rd grade in Seoul. The location of crossing visual axes were derived from the relation of the binocular disparity and the PD for the adults and children. Results: The average PD of the children was measured to be 57.3 mm which was smaller than the average PD of the adults that was known to be about 65 mm. As the binocular disparity increases to the positive direction, the crossing location steeply moves farther behind the screen. On the other hand, when the binocular disparity increases to the negative direction, the crossing location gradually moves toward the viewer. For the same amount of the binocular disparity, the crossing locations were derived to be larger for the children than the adults due to the difference of the PD. Therefore, children will perceive larger depth than the adults. Conclusions: Small PD of the viewer causes the larger amount of the depth perception. In producing the stereoscopic images, the average PD of children as well as adults need to be considered.