• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.04b
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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.

• Journal of the Korean Society of Visualization
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• v.8 no.4
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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.

• Korean Journal of Optics and Photonics
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• v.7 no.3
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• pp.280-286
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• 1996

This paper describes operation mechanism of a novel optical waveguide phase modulator with optical bistability characteristics by self electro-optic effect. The fabricated device structure is an optical waveguide modulator, using a refractive index change by an applied electric field, parallel integrated with SEED with an electrical bistability. GaAs/AlGaAs MQW is used as the core layer of the waveguide modulator and the absorption layer of SEED. The absorbed optical power in SEED changes the diode voltage and controls the optical power propagating through the waveguide phase modulator. Optical bistability of waveguide phase modulator is experimentally obtained by using electrical bistability of SEED. Compared to other waveguide modulators, the proposed one has an asset that the lowest optical power is required to generate optical bistability.

• Journal of the Optical Society of Korea
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• v.14 no.2
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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.

• Current Optics and Photonics
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• v.6 no.1
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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.

• Journal of Information Display
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• v.4 no.3
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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.

• Proceedings of the Materials Research Society of Korea Conference
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• 2006.05a
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• pp.21.1-21.1
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• 2006

• Journal of the Optical Society of Korea
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• v.20 no.6
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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.

• 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.

• 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.