• 제목/요약/키워드: Bistability

검색결과 60건 처리시간 0.026초

DFB SOA의 광쌍안정 특성을 이용한 전광논리구현 (All Optical Logic Gate Based On Optical Bistability of DFB SOA)

  • 김병채;김영일;이석;우덕하;윤태훈
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2002년도 춘계학술대회 논문집 디스플레이 광소자 분야
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    • pp.112-113
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    • 2002
  • Optical bistability can be applied to the optical logic. optical signal processing and optical memory. We have measured the optical bistability of DFB-SOA and demonstrated all-optical OR logic gate using switching characteristics of DFB-SOA.

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마이크로 채널 내부에서의 액적의 쌍안정성과 이를 활용한 유동 제어 (Droplet Bistability in Microchannel and its Application to Flow Control)

  • 이범준;유정열
    • 한국가시화정보학회지
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    • 제8권4호
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    • pp.43-47
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    • 2010
  • We demonstrate the droplet bistability in a microchannel which has two symmetric necks that operate as capillary valves. It is shown that there are certain flow conditions, determined by droplet velocity and droplet size, to achieve bistability. Droplet bistabililty allows simple but precise control of droplet at a bifurcation channel. Therefore, by an appropriate channel design to induce droplet bistability, we can distribute droplets at a junction passively in the manner of perfect alternation and perfect switching in the choice of the outlets.

광쌍안정을 갖는 GaAs/AlGaAs MQW 도파로형 위상 광변조기 (GaAs/AlGaAs MQW waveguide phase modulator with optical bistability)

    • 한국광학회지
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    • 제7권3호
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    • pp.280-286
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    • 1996
  • 본 논문에서는 자기 전광 효과를 이용하여 광쌍안정을 갖는 새로운 형태의 도파로형 광변조기의 동작 특성에 관하여 논하였다. 제작된 소자는 전계의 세기에 따른 굴절률의 변화를 이용하는 위상 변조형 광변조기와 전기적 쌍안정성을 갖는 수광 소자가 병렬로 연결된 구조로 되어 있다. 광도파로층과 수광 소자의 흡수층은 GaAs/AlGaAs 다중 양자 우물층을 사용하였다. 수광 소자에 흡수되는 광의 세기에 따라 변하는 다이오드 전압은 도파로형 광변조기를 통과하는 광의 세기를 조절하며 SEED의 전기적 쌍안정을 이용하여 도파로형 광변조기의 광쌍안정을 얻을 수 있었다. 본 논문에서 제안된 광변조기는 기존의 도파로형 광변조기에 비해 낮은 입력광에서도 광안쌍정을 갖는 장점을 갖는다.

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All-optical Flip-flop Operation Based on Polarization Bistability of Conventional-type 1.55-㎛ Wavelength Single-mode VCSELs

  • Lee, Seoung-Hun;Jung, Hae-Won;Kim, Kyong-Hon;Lee, Min-Hee
    • Journal of the Optical Society of Korea
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    • 제14권2호
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    • pp.137-141
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    • 2010
  • We report, for the first time to our knowledge, observation of polarization bistability from 1.55-${\mu}m$ wavelength single-mode VCSELs of a conventional cylinder-shape under control of their driving current, and demonstration of all-optical flip-flop (AOFF) operations based on the bistability with optical set and reset pulse injection at a 50 MHz switching frequency. The injection pulse energy was less than 14 fJ. The average on-off contrast ratio of the flip-flopped signals was about 7 dB. These properties of the VCSELs will be potentially useful for future high-speed all-optical signal processing applications.

Low-threshold Optical Bistability Based on Bound States in the Continuum

  • Kim, Myunghwan;Kim, Sangin;Kim, Soeun
    • Current Optics and Photonics
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    • 제6권1호
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    • pp.10-14
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    • 2022
  • Low-threshold optical bistability is essential for practical nonlinear optical applications. Many bistable optical devices based on high-quality-factor resonators have been proposed to reduce the threshold intensity. However, demonstrating high-quality-factor resonance requires complex fabrication techniques. In this work, we numerically demonstrate optical bistability with bound states in the continuum in a simple one-dimensional Si photonic crystal. The designed structure supports bound states in the continuum, producing an ultrahigh quality factor without tough fabrication conditions. The threshold intensity of the designed device is 150 MW/cm2 at the optical communication wavelength. This scheme may lead to a new class of nonlinear photonics.

Bragg Reflective Polymer Stabilized Cholesteric Liquid Crystal Display

  • Kwon, Jang-Un;Kang, Dae-Seung
    • Journal of Information Display
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    • 제4권3호
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    • pp.26-28
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    • 2003
  • In the paper, we investigated the Bragg reflective cholesteric display based on polymer stabilization. We studied the bistability in the polymer stabilized cholesteric texture (PSCT) films and baused on which we achieved wider viewing angle though imperfect planar texture.

All-optical Flip-flop based on Optical Beating and Bistability in an Injection-locked Fabry-Perot Laser Diode

  • Kim, Junsu;Lee, Hyuek Jae;Park, Chang-Soo
    • Journal of the Optical Society of Korea
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    • 제20권6호
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    • pp.698-703
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    • 2016
  • We report a new all-optical flip-flop (AOFF) with a quite simple structure, using optical beating in an injection-locked Fabry-Perot laser diode (FP-LD) with optical bistability. While conventional AOFF methods using an injection-locked FP-LD require additional devices such as secondary FP-LDs or polarization controllers for reset operation, the proposed method can be implemented using only a single commercially available FP-LD with set and reset signals. The optical beating induces intensity fluctuations inside the FP-LD, and releases the locking state to the reset state. Even though we demonstrated the AOFF at 100 Mbit/s, we expect that its operation rate could extend to 10 Gbit/s, according to the limit of the FP-LD's frequency response.

Bistability of $Co^{III}$(N-N)(3,6-DBSQ)(3,6-DBCat):Subtle Diimine Ligand Effect (N-N=4,7-Dimethyl-1,10-phenanthroline, 5-Chloro-1,10-phenanthroline;DBSQ=Di-tert-butylsemiquinonato;DBCat=Di-tert-butylcatecholato)

  • Ok-Sang Jung;Young-A Lee;Younkyoo Kim;Youn Soo Sohn
    • Bulletin of the Korean Chemical Society
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    • 제15권8호
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    • pp.641-643
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    • 1994
  • Studies of Co(N-N)(3,6-DBSQ)(3,6-DBCat)(N-N=4,7-dimethyl-1 ,10-phenanthroline, 5-chloro-1,10-phenanthroline; DBSQ=di-tert-butylsemiquinonato; DBCat=di-tert-butylcatecholato) have been carried out on the bistability by intramolecular cobalt-quinone electron transfer in solid state. The title complexes dominantly exist as $Co^{III}$(N-N)(3,6-DBSQ)(3,6-DBCat) at room temperature and display a significant bistability on temperature variation. Subtle change in optical spectra and magnetic properties is observed when diimine ligands are changed.

전기 광학적 궤환을 이용한 광 쌍안정성과 다 안정성 (Optical Bistability and Multistability Using Electro-Optic Feedback)

  • 이창희;조건호;신상영;이수영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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    • pp.64-67
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    • 1987
  • We demonstrate the optical bistability and multistability using light emitting devices, a photodetector, and transistors under the positive electro optic feedback. Its operating principle and high speed operation Scheme are also described.

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