• Title/Summary/Keyword: Optical bistability

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

  • Lee, Chang-Hee;Cho, Kun-Ho;Shin, Sang-Yung;Lee, Soo-Young
    • Proceedings of the KIEE Conference
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    • 1987.07a
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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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Effect of Chirped Grating on Optical Bistability in λ/4-shifted Semiconductor DFB Devices

  • Kim, Young-Il;Yoon, Tae-Hoon;Lee, Seok;Kim, Sun-Ho
    • Journal of the Optical Society of Korea
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    • v.5 no.1
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    • pp.5-8
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    • 2001
  • In this work, we studied the effect of chirped grating on optical bistability in λ/4-shifted semiconductor distributed-feedback(DFB) devices, such as an etalon with nonlinear mirrors, a λ/4-shifted DFB waveguide and aλ/4-shifted DFB laser amplifier. We found that chirped DFB devices exhibit bistable switching at a lower input power.OCIS code : 050.2770, 190.1450, 190.5970, 230.0230.

Polarization Bistability in a Feedback Hybrid Opto-electronic Device (되먹임 혼성 광 간섭계에서의 편광 광쌍안정)

  • 김성규;유영훈;임동건
    • Korean Journal of Optics and Photonics
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    • v.2 no.1
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    • pp.26-30
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    • 1991
  • TO study the polarization optical bistability (POB), we constructed the hybrid opto-electronic interferometer which has orthogonal polarized lights and one of the optical phases is modulated by a feedback signal. And we developed the theoretical POB equation for this system and observed the POB by varying input intensity of the light and initial phase experimentally.

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Phenomenon of the absorptive optical bistabililty in amorphous $As_2S_3$ thin film (비정질 $As_2S_3$ 박막에서의 흡수형 광쌍안정 현상)

  • 안웅득;김석원;한성홍
    • Korean Journal of Optics and Photonics
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    • v.7 no.2
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    • pp.129-135
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    • 1996
  • We observed the absorptive optical bistability in the single layer amorphous $As_2S_3$ thin film which has an isolated electron pairs at roomtemperature, for the frist time, $Ar^+$ laser beam (λ=514.5 nm) was used as a light source and was focused by thin lens. The experiment was performed in cavityless system and the occurrence of optical bistability in this material could be explained by the temperature-dependent absorption coefficient of the sample. Also, this effect was explained by the reversible shift of the absorption edge in this material. The condition of optical bistability is determined by detuning value ($a_0L$) and this value was 0.12 when thikness of that sample was about 0.8 ${\mu}{\textrm}{m}$. The switching was observed clealy when light intensity is 150~180 mW and the swiching time was about $10^{-4}$ s.

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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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    • v.15 no.8
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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.

A Simple Analytical Model for the Study of Optical Bistability Using Multiple Quantum Well p-i-n Diode Structure

  • Jit, S.;Pal, B.B.
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.4 no.1
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    • pp.63-73
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    • 2004
  • A simple analytical model has been presented for the study of the optical bistability using a $GaAs-Al_{0.32}Ga_{0.68}As$ multiple quantum well (MQW) p-i-n diode structure. The calculation of the optical absorption is based on a semi-emperical model which is accurately valid for a range of wells between 5 and 20 nm and the electric field F< 200kV/cm . The electric field dependent analytical expression for the responsivity is presented. An attempt has been made to derive the analytical relationship between the incident optical power ( $(P_{in})$ ) and the voltage V across the device when the diode is reverse biased by a power supply in series with a load resistor. The relationship between $P_{in}$ and $P_{out}$ (i.e. transmitted optical power) is also presented. Numerical results are presented for a typical case of well size $L_Z=10.5nm,\;barrier\;size\;L_B=9.5nm$ optical wave length l = 851.7nm and electric field F? 100kV/cm. It has been shown that for the values of $P_{in}$ within certain range, the device changes its state in such a way that corresponding to every value of $P_{in}$ , two stable states and one unstable state of V as well as of $P_{out}$ are obtained which shows the optically controlled bistable nature of the device.

Nonlinear guided-wave properties in planar waveguides with two nonlinear bounding thin films (비선형 박막으로 둘러싸인 평면 광도파로에서의 비선형 도파광 특성)

  • 정종술;송석호;이일항
    • Korean Journal of Optics and Photonics
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    • v.7 no.2
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    • pp.136-141
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    • 1996
  • We present a novel description of TE nonlinear guided waves in planar waveguides with two nonlinear bounding thin films. The nonlinear dispersion relations of the nonlinear waveguides are obtained by adopting the nonlinear transfer matrix. The optical properties obtained from these equations include: the power dependence of mode indices, the transition of the field maximum location, and the power distribution. The planar waveguide with self-focusing nonlinear layers shows the optical bistability of power-dependent mode indices, and the critical powers for the optical bistability increase with decreasing thickness of the nonlinear layers. The power distributions display the optical bistabilities, similar to those of nonlinear Fabry-Perot etalon.

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