• 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.

• Proceedings of the Optical Society of Korea Conference
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• 1990.02a
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• pp.95-101
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• 1990

Parallel optical arithmetic techniques have been developed using the correlation property of optical phase conjugate wave generated by degenerated four wave-mixing. In this paper, conventional rectangular-type coded pattern used for optical logic system is replaced by circular one for effective beam coupling in a photorefractive $BaTiO_3$ material. By adequately adjusting the distance between circular-type pixels of the input pattern and grouping the correlated output, optical binary half addition/subtraction, binary multiplication and, matrix-matrix computation are demonstrated.

• Journal of Photoscience
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• v.9 no.2
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• pp.317-319
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• 2002

All-optical switching has been demonstrated in bacteriorhodopsin (bR) based on nonlinear intensity induced excited state absorption. The transmission of a cw probe laser beam at 410 nm corresponding to the peak absorption of M state through a bR film is switched by a pulsed pump laser beam at 570 nm that corresponds to the maximum initial 8 state absorption. The switching characteristics have been analyzed using the rate equation approach considering all the six intermediate states (B, K, L, M, N and 0) in the bR photocycle. The switching characteristics are shown to be sensitive to life time of the M state, absorption cross-section of the 8 state at probe wavelength ($\sigma$ $\_$Bp/) and peak pump intensity. It has been shown that the probe laser beam can be completely switched off (100 % modulation) by the pump laser beam at relatively low pump powers, for $\sigma$$\_$Bp/ = O. The switching characteristics have been used to design all-optical NOT, OR, AND and the universal NOR and NAND logic gates for optical computing with two pulsed pump laser beams.

• Proceedings of the Optical Society of Korea Conference
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• 2005.02a
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• pp.168-169
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• 2005

• Proceedings of the Optical Society of Korea Conference
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• 2004.07a
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• pp.182-183
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• 2004

• Proceedings of the Optical Society of Korea Conference
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• 2007.07a
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• pp.337-338
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• 2007

• Proceedings of the Optical Society of Korea Conference
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• 2004.02a
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• pp.262-263
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• 2004

• Journal of IKEEE
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• v.18 no.3
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• pp.328-334
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• 2014

This paper proposes an optical encryption and decryption system for OFB(Output Feedback Block) encryption algorithm. The proposed scheme uses a dual-encoding technique in order to implement optical XOR logic operation. Also, the proposed method provides more enhanced security strength than the conventional electronic OFB method due to the huge security key with 2-dimensional array. Finally, computer simulation results of encryption and decryption are shown to verify the proposed method, and hence the proposed method makes it possible to implement more effective and stronger optical block encryption system with high-speed performance and the benefits of parallelism.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.1
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• pp.76-89
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• 2013

In this paper, we propose a novel optical fault detection scheme for RSA hardware based on Montgomery exponentiation, which can effectively detect optical fault injection during the exponent calculation. To protect the RSA hardware from the optical fault injection attack, we implemented integrity check logic for memory and optical fault detection logic for Montgomery-based multiplier. The proposed scheme is considered to be safe from various type of attack and it can be implemented with no additional operation time and small area overhead which is less than 3%.

• Korean Journal of Optics and Photonics
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• v.23 no.4
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• pp.143-146
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• 2012

All-optical data extraction, one of the key technologies for all-optical computing and optical communication to perform add-drop, packet switching, and data reset, etc., is experimentally demonstrated by using cross-gain modulation (XGM) of semiconductor optical amplifiers (SOAs). Also, all-optical data extraction based on numerical simulation is performed by using the VPI simulation tool. In this paper, the suggested optical system based on SOAs shows the potential for high speed, and highly integrable and low power optical data computing.