• Title/Summary/Keyword: second harmonic

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An approach based on the generalized ILOWHM operators to group decision making

  • Park, Jin-Han;Park, Yong-Beom;Lee, Bu-Young;Son, Mi-Jung
    • Journal of the Korean Institute of Intelligent Systems
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    • v.20 no.3
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    • pp.434-440
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    • 2010
  • In this paper, we define generalized induced linguistic aggregation operator called generalized induced linguistic ordered weighted harmonic mean(GILOWHM) operator. Each object processed by this operator consists of three components, where the first component represents the importance degree or character of the second component, and the second component isused to induce an ordering, through the first component, over the third components which are linguistic variables and then aggregated. It is shown that the induced linguistic ordered weighted harmonic mean(ILOWHM) operator and linguistic ordered weighted harmonic mean(LOWHM) operator are the special cases of the GILOWHM operator. Based on the GILOWHM and LWHM operators, we develop an approach to group decision making with linguistic preference relations. Finally, a numerical example is used to illustrate the applicability of the proposed approach.

Cerenkov type second harmonic genration in poled polymer waveguide (폴링된 폴리머 광도파로를 이용한 cerenkov형 제2고조파 생성)

  • 김응수;조원주
    • Journal of the Korean Institute of Telematics and Electronics D
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    • v.35D no.8
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    • pp.62-68
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    • 1998
  • Optical broadband second harmonic genration (SHG) in thin film waveguide structure was investigated. The copolymer poly(MMA-co-DR1MA) which was consiste dof PMMA (polymethylmethacrylate) and DR 1 (disperse red 1) was spin coated on the pyrex substrate. The green and near UV SHG were observe dfrom the fundamental beam even though the poled polymer has the absorption in second harmonic wavelength range. It was able to genrate SHG by cerenkov type phase matching. Th epoled polymer film thickness was decided by theoretical analysis. The green (532nm) and near UV SHG (370nm) were observed from the Q-switched Nd-YAG laser (1064nm) and Ti-sapphire laser (740nm). It was in good agreement with the experimental results.

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Efficient Second Harmonic Generation of Pulsed Nd-YAG Laser Radiation with Noncritically Phase-Matchable $LiNbO_3$ in Room-Temperature

  • Jong-Soo Lee;Bong-Hoon Kang;Bum Ku Rhee;Chong-Don Kim;Gi-Tae Joo
    • The Korean Journal of Ceramics
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    • v.6 no.3
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    • pp.206-208
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    • 2000
  • 0.65 mol% MgO-doped LiNbO$_3$single crystals were grown by CZ method. The obtained single crystals were colorless and transparent. Noncritically phase-matched second harmonic generation (SHG) of 532-nm radiation from 1064-nm in MgO-doped LiNbO$_3$has been investigated by using pulsed Nd:YAG laser. The phase-matching temperature was room temperature. SHG conversion efficiencies were typically achieved higher than 50% at the phase-matching temperature with no photorefractive damage in the region of fundamental power density which was used in this experiment. The thermo-birefringence coefficient and the electro-birefringence coefficient of SHG were calculated from the temperature phase-matching profile with the electric field.

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Second harmonic generation of YCOB($YCa_4O(BO_3)_3$) (YCOB($YCa_4O(BO_3)_3$)의 제2조화파 발생)

  • 장원권
    • Korean Journal of Optics and Photonics
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    • v.10 no.4
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    • pp.301-305
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    • 1999
  • The phase matching conditions of the new optical crystal grown by Czochralski pulling method, YCOB($YCa_4O(BO_3)_3$) with wavelength were suggested, and the second harmonic generation efficiency for the fundamental of Nd:YAG laser of 1064 nm was investigated. The variation of nonlinearity with rare earth ion doping was also investigated by measuring the second harmonic generation efficiencies of $Yb^{3+}$ + $Nd^{3+}$and ion doped YCOBs.

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Second Harmonic Generation on the Surface of Porous Silicon Superlattice (초격자 다공질규소 표면에서 제 2고조파 발생)

  • Cho, Chang-Ho;Park, Jong-Dae
    • The Journal of Natural Sciences
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    • v.12 no.1
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    • pp.31-39
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    • 2002
  • Second harmonic generation was measured in porous silicon superlattices surface which were made by changing and anodization current density and the anodization time periodically in the process of obtaining porous silicon. The technique of second harmonic generation is used as a probe to the surface of porous silicon superlattice by using Nd:YAG laser. We have investigated the surface structure and nonlinear-optics properties of porous silicon superlattice.

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Novel Oscillator Incorporating a Compact Microstrip Ring Type Resonant Cell with High Efficiency and Superior Harmonic Characteristics

  • Hwang Cheol-Gyu;Myung Noh-Hoon
    • Journal of electromagnetic engineering and science
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    • v.5 no.2
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    • pp.92-96
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    • 2005
  • This paper presents a novel microwave oscillator incorporating a simple microstrip ring type resonant cell as its terminating resonance component. Reduced chip size, higher dc-ac power efficiency, superior harmonic characteristics can be achieved from the introduction of a compact microstrip ring resonator cell. The oscillator provides a second harmonic suppression of 26.51 dB and the output power of 2.046 dBm at 2.11 GHz.

Gold-sapphire Plasmonic Nanostructures for Coherent Extreme-ultraviolet Pulse Generation

  • Han, Seunghwoi
    • Current Optics and Photonics
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    • v.6 no.6
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    • pp.576-582
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    • 2022
  • Plasmonic high-order harmonic generation (HHG) is used in nanoscale optical applications because it can help in realizing a compact coherent ultrashort pulse generator on the nanoscale, using plasmonic field enhancement. The plasmonic amplification of nanostructures induces nonlinear optical phenomena such as second-order harmonic generation, third-order harmonic generation, frequency mixing, and HHG. This amplification also causes damage to the structure itself. In this study, the plasmonic amplification according to the design of a metal-coated sapphire conical structure is theoretically calculated, and we analyze the effects of this optical amplification on HHG and damage to the sample.

Q-Switched Nd YAG's SHG conversion techniques for a skin diseased treatment (피부질환 치료를 위한 Q-Switched Nd:YAG의 SHG 변환기술)

  • Kim, Whi-Young
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.13 no.6
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    • pp.1141-1149
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    • 2009
  • Pulse style Nd: YAG Laser is suitable in skin remaking treatment, in compliance with the ramp continuous oscillation until of course normal takeoff, the Q-switch and mode motive takeoff the takeoff form which is various is possible and it is coming to be widely used in microsurgery and skin remaking promotion. According to therapeutic objective very it is important to control a energy density. Control of energy density the method which controls the pulse repetition rate of Laser output is mainly used. From the research which it sees pulse style Nd: It will be able to control the pulse repetition rate of YAG, the 2nd harmonic occurrence Laser (second harmonic generation: SHG) with the energy part of the light-wave which is a footnote wave number will hold and nonlinear decision it propagates and is converted by energy of the light-wave which is a footnote wave number the actual condition which and it applies the second harmonic occurrence in compliance with a secondary nonlinearity it leads and until skin deep part therapeutic possibility is the thing it will be able to observe simply.

Mono- and Multi-layer Langmuir-Blodgett Films of Maleimide Polymers Possessing Nonlinear Optical-Active Side Chains

  • Yoon Kuk Ro;Lee Hoosung;Rhee Bum Ku;Jung Changsoo
    • Macromolecular Research
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    • v.12 no.6
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    • pp.581-585
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    • 2004
  • A copolymer P[OSA-MI] was synthesized by copolymerization of its corresponding monomers, N-phenyl maleimide (MI) and 2-octen-l-ylsuccinic anhydride (OSA). The polymer (poly[2-[1-(2,5-dioxo-l-phenylpyrroli­din-3-ylmethyl)heptyl]-succinic acid 4-(2-$\{$ethyl-[4-(4-nitrophen-ylazo)phenyl]amino$\}$ethyl)ester]) P[DR1MA-MI] was obtained from the reaction of P[OSA-MI] with 2-[4-(4-nitrophenylazo)-N-ethylphenylamino] ethanol (DR1). A stable monolayer of P[DRIMA-MI] was formed by spreading the solution of the polymer in chloroform. In Y-type Langmuir-Blodgett (LB) films prepared using this Langmuir-Blodgett method, the second harmonic waves generated from adjacent mono layers canceled each other out. In X-and Z-type LB films, the second harmonic intensity increased upon increasing the number of monolayers, but this increase was somewhat smaller than predicted by the square law. This phenomenon is due to defects or imperfect alignment of the dipoles in the LB film. The generation of second harmonic waves from Y-type LB films having an even number of mono layers supports this argument. The degree of imperfection seemed to increase as the number of layers increased. The second-order nonlinear optical properties of spin-cast films of these polymers were also measured. The largest second harmonic coefficient of the poled P[DRIMA-MI] film coated on a glass plate was 19 pm/V.