• 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 Optical Society of Korea
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• v.19 no.3
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• pp.222-227
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• 2015

We propose a new and potentially integrable scheme for the realization of an all-optical binary full adder employing two XOR gates, two AND gates, and one OR gate. The XOR gate is realized using a Mach-Zehnder interferometer (MZI) based on a semiconductor optical amplifier (SOA). The AND and OR gates are based on the nonlinear properties of a semiconductor optical amplifier. The proposed scheme is driven by two input data streams and a carry bit from the previous less-significant bit order position. In our proposed design, we achieve extinction ratios for Sum and Carry output signals of 10 dB and 12 dB respectively. Successful operation of the system is demonstrated at 10 Gb/s with return-to-zero modulated signals.

• IEIE Transactions on Smart Processing and Computing
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• v.5 no.1
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• pp.5-9
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• 2016

The modulation bandwidth of a reflective semiconductor optical amplifier (RSOA) is limited by carrier lifetime. Therefore, it is hard to directly modulate an RSOA with high-speed electrical signals. We theorize that an optical filter can act as an optical equalizer, compensating for the narrow bandwidth limitation imposed by the RSOA. By modeling a time-varying RSOA with a modified transfer matrix method (TMM), we simulated 25 Gbps operation of an RSOA with optical filtering effects. We investigated the impact of detuning the center wavelength of the optical filter on the modulation of an RSOA. The numerical results show that it is possible to modulate an RSOA with an optical filtering effect at 25 Gbps without electronic equalization or digital signal processing.

• Journal of the Optical Society of Korea
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• v.10 no.1
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• pp.11-15
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• 2006

We have proposed and theoretically verified an optical regenerator using a single semi-reflective semiconductor optical amplifier (SR-SOA). To explain the operation characteristics and the operation condition of the proposed opticalregenerator, the simplified gain model for the SR-SOA is introduced and confirmed by comparing the result of the SOA simulation based on the transfer matrix method (TMM). The simulation results show that both extinction ratio (ER) enhancement and signal amplification can be achieved in the proposed regenerator.

• Korean Journal of Optics and Photonics
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• v.13 no.5
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• pp.421-424
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• 2002

By using SOA (Semiconductor Optical Amplifier) based devices, an all-optical half adder has been successfully demonstrated at 10 Gb/s. All-optical XOR and AND gates are utilized to realize SUM and CARRY. Since SUM and CARRY have been simultaneously realized to form the all-optical half adder, complex calculation and signal processing can be achieved.

• Korean Journal of Optics and Photonics
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• v.10 no.4
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• pp.294-300
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• 1999

The density matrix is solved more rigorously, compared with the third-order pertubation method used in the conventional theory, for a semiconductor laser amplifier. Then the coupled wave equations are derived to explain the wavelength conversion due to the spectral hole burning in the semiconductor optical amplifier. It is shown that our results can explain the effect of saturation of the population density on the electric polarization, which affects the four-wave mixing and wavelength conversion, better than the conventional theroy where the third-order pertubation is used.

• Korean Journal of Optics and Photonics
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• v.29 no.1
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• pp.32-39
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• 2018

The impact of the amplified spontaneous emission (ASE) on the gain recovery time of a bulk semiconductor optical amplifier (SOA) is investigated. The gain-recovery time is obtained by determining the time evolution of the gain, carrier density, and ASE in an SOA, after the propagation of a short pump pulse and continuous-wave (CW) probe of gain dynamics. In the simulation, a wide-band-semiconductor model, which can be characterized by the material gain coefficient over a wide wavelength range, is used, because the gain bandwidth of a practical SOA is very wide. The pump pulse and counterpropagating CW probe field are considered in the simulation, with the ASE noise spectrum equally divided.

• Current Optics and Photonics
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• v.2 no.5
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• pp.400-406
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• 2018

The Semiconductor Optical Amplifier (SOA)-based Mach-Zehnder interferometer is a major contributor in all-optical digital processing and optical computation. Optical tree architecture provides one of the new, alternative schemes for integrated all-optical arithmetic and logical operations. In this paper, we propose an all-optical 3-bit integrated parity generator and checker using SOA-MZI-based optical tree architecture. The proposed scheme, able to process input signals at a desired operating wavelength, has been characterized using RZ-modulated signals at 10 Gbps. The maximum extinction ratios achieved at the output of the parity generator and checker are 10 dB and 8 dB respectively.

• Proceedings of the Optical Society of Korea Conference
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• 1998.08a
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• pp.214-215
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• 1998

• Proceedings of the Optical Society of Korea Conference
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• 1999.08a
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• pp.224-225
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• 1999