• 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.

• Korean Journal of Optics and Photonics
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• v.13 no.2
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• pp.151-154
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• 2002

All-optical OR logic gate is realized by use of gain saturation and wavelength conversion in the semiconductor optical amplifiers (SOA). It is operated by the nonlinearity of the SOA gain and hence to obtain the sufficient gain saturation of the SOA, pump signals are amplified by an Er-doped fiber amplifier (EDFA) at the input of the SOA. The operation characteristics of all-optical OR logic gate are successfully measured at 2.5 Gbit/s.

• Korean Journal of Optics and Photonics
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• v.14 no.5
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• pp.530-534
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• 2003

A novel all-optical NOR gate is proposed and demonstrated for the first time by use of gain saturation in a semiconductor optical amplifier (SOA). It is operated by the nonlinearity of the SOA gain. Hence, to obtain sufficient gain saturation of the SOA, pump signals are amplified by an Er-doped fiber amplifier at the input of the SOA. The operation characteristics of the all-optical NOR gate are successfully measured at 10 Gbit/s.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.8
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• pp.1580-1584
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• 2009

We have theoretically analyzed the monolithic integration of vertical cavity lasers with depleted optical thyristor (VCL-DOT) structure and experimentally demonstrated optical logic gates such as AND-gate, OR-gate, and INVERTER implemented by VCL-DOT for an optical programmable gate array. The optical AND and OR gates have been realized by changing a input bias of the single VCL-DOTs and all kinds of optical logic functions are also implemented by adjusting an intensity of the reference input beams into the differential VCL-DOTs. To achieve the high sensitivity, high slope efficiency and low threshold current, a small active region of lasing part and a wide detecting area are simultaneously designed by using a selective oxidation process. The fabricated devices clearly show nonlinear s-shaped current-voltage characteristics and lasing characteristics of a low threshold current with 0.65 mA and output spectrum at 854 nm.

• Proceedings of the Optical Society of Korea Conference
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• 2001.02a
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• pp.148-149
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• 2001

순광학적 스위치와 logic gate는 초고속 networks와 컴퓨터를 위한 차세대의 기술로 부각되고 있다. 현재 사용되고 있는 전자적인 switching, routing, 신호 처리들은 대용량 고속화에 그 한계를 나타내고 있다. 미래에 요구되는 초고속 광 네트워크의 계획은 광학 스위치와 광 변조장치가 필요하다는 것을 지적하고있다 최근에 전자나 광전자적으로 가능한 것 이상으로 미래에 요구되는 Tera bits/sec에 접근할 수 있는 고속 연산과 신호처리가 가능한 스위칭에 관한 연구가 활발이 진행되고 있다. (중략)

• Journal of the Optical Society of Korea
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• v.18 no.6
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• pp.639-645
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• 2014

In this paper, the scheme of a single module for simultaneous operation of all-optical computing circuits, namely half adder and half subtractor, are realized using semiconductor optical amplifier (SOA) based logic gates. Optical XOR gate by employing a SOA based Mach-Zehnder interferometer (MZI) configuration is used to get the sum and difference outputs. A carry signal is generated using a SOA-four wave mixing (FWM) based AND gate, whereas, the borrow is generated by employing the SOA-cross gain modulation (XGM) effect. The obtained results confirm the feasibility of our configuration by proving the good level of quality factor i.e. ~5.5, 9.95 and 12.51 for sum/difference, carry and borrow, respectively at 0 dBm of input power.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.04b
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• pp.109-111
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• 2002

We have demonstrated all-opticalflip-flop based on optical bistability in a SOA/DFB-SOA with broadband gain. Input signal with the wavelength of 1340.23 nm or 1680.93 nm and the current of about 98% of the lasing threshold is injected into theDFB-SOA. Current injected into SOA is 80 mA All-optical flip-flop has various applications such as all-optical memory, demultiplexing, packet-header buffering, and retiming.

• Korean Journal of Optics and Photonics
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• v.13 no.1
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• pp.84-87
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• 2002

By using SOA (Semiconductor Optical Amplifier), all-optical XOR gate has been demonstrated at 5 Gb/s in RZ format. Firstly, Boolean AB-and Boolean AB have been obtained. Then, Boolean AB and Boolean AB have been combined to achieve the all-optical XOR gate, which has Boolean logic of AB+AB.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.1 s.343
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• pp.13-16
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• 2006

We have proposed and experimentally demonstrated the all-optical composite logic gates with XOR, NOR, OR and NAND functions using SOA-MZI structures to make it possible to simultaneously perform various logical functions. The proposed scheme is robust and feasible for high speed all-optical logic operation with high ER.

• Journal of the Optical Society of Korea
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• v.16 no.4
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• pp.432-442
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• 2012

In this paper, we propose, analyze and simulate the performances of some new plasmonic logic gates in two dimensional plasmonic waveguides with nanodisk resonators, using the numerical method of finite difference time domain (FDTD). These gates, including XOR, XNOR, NAND, and NOT, can provide the highly integrated optical logic circuits. Also, by cascading and combining these basic logic gates, any logic operation can be realized. These devices can be utilized significantly in optical processing and telecommunication devices.