Chang Wan Son

All-optical half adder using cross gain modulation in semiconductor optical amplifiers

By using the gain nonlinearity characteristics of semiconductor optical amplifier, an all-optical binary half adder at 10 Gbps is demonstrated. The half adder operates in a single mechanism, which is cross gain modulation. The half adder utilizes two logic functions of SUM and CARRY, which can be demonstrated by using XOR and AND gates, respectively. The extinction ratios of both XOR and AND gates are about 6.1 dB. By achieving this experiment, we also explored the possibilities for the enhanced complex logic operation and higher chances for multiple logic integration.

One-Level Simplification Method for All-Optical Combinational Logic Circuits

We propose a novel one-level simplification method for all-optical combinational logic circuits. With the proposed method, an all-optical gray code to binary coded decimal converter is successfully developed for the first time by using conventional semiconductor optical amplifiers as building elements. In comparison to the construction algorithm based on the conventional two-level simplification method, a significant improvement is observed in the Q-factor.

Implementation of All-Optical Logic AND using XGM based on Semiconductor Optical Amplifiers

By using two input signals of A and B, an all-optical AND gate that utilize a XGM in semiconductor optical amplifiers is demonstrated at 10 Gbps. By achieving this experiment, it will be also explored the possibilities for the enhanced complex logic.

Realization of all-optical full adder using cross-gain modulation

An all-optical full adder using semiconductor optical amplifiers has been demonstrated at 10 Gbps for the first time. The full adder consisted of XOR and NOR gates only utilizes the mechanism of cross-gain modulation. The full adder utilize two logic functions of SUM and CARRY, which can be demonstrated by using two XOR gates and four NOR gates, respectively. By passing signal A as probe signal and signal B as pump signal into SOA-1, Boolean A NOT B can be obtained. Also, by changing the role of signals A and B for SOA-2, Boolean NOT A B can be acquired. Addition of Boolean A NOT B and NOT A B results in NOT A B + A NOT B , which is Boolean expression of logic XOR. By passing this XOR signal and signal C into the second XOR gate with the same principle, SUM signal of the full adder can be obtained. The Boolean expression of SUM can be expressed as A # B # C . With the first three NOR gates, Boolean NOT(A+B), NOT(B+C), and NOT(C+A) can be obtained. With the addition of these outputs, Boolean NOT(A+B) + NOT(B+C) + NOT(C+A) can be formed. By injecting these outputs through the last NOR gate with clock signal, CARRY signal of the full adder can be realized. The Boolean expression of CARRY can be expressed as AB +BC +CA. The extinction ratio is about 6.1dB.

All-Optical Digital Logic Circuit based on NOR-Only Two-Level Simplification Method

For the first time, we suggest the application of NOR-only two-level simplification method for the construction of flexible all-optical digital logic circuit. Arbitrary Boolean function operation and decoding of gray code to binary coded decimal (BCD) are demonstrated with the suggested approach.

Realization of all-optical half adder using XGM in semiconductor optical amplifiers without additional input beam

By using gain nonlinearity characteristics of semiconductor optical amplifier, an all-optical binary half adder at 10 Gbps is demonstrated. No additional input beam such as clock signal or continuous wave light, which is required in many other all-optical logic gates, is used in this design concept. The half adder operates in single mechanism, which is XGM.

All-optical half adder using single mechanism of XGM in semiconductor optical amplifiers

By using gain nonlinearity characteristics of semiconductor optical amplifier, an all-optical binary half adder at 10 Gbps is demonstrated. The half adder operates in single mechanism, which is XGM. The half adder utilizes two logic functions of SUM and CARRY, which can be demonstrated by using the XOR gate and the AND gate, respectively. In the XOR (A NOT B + NOT A B) gate, Boolean A NOT B is obtained by using signal A as a probe beam and signal B as a pump beam in SOA-1. Also, Boolean NOT A B is obtained by using signal B as a probe beam and signal A as a pump beam in SOA-2. By adding two outputs from SOA-1 and SOA-2, Boolean A NOT B + NOT A B (logic XOR) can be obtained. In the AND (AB ) gate, Boolean NOT B is firstly obtained by using signal B as a pump beam and clock signal as a probe beam in SOA-3. By passing signal A as a probe beam and NOT B as a pump beam through SOA-4, Boolean AB is acquired. By achieving this experiment, we also explored the possibilities for the enhanced complex logic operation and higher chances for multiple logic integration.

Demonstration of 10 Gbps Optical Encryption and Decryption by Using Semiconductor Optical Amplifiers

Optical encryption and decryption system is successfully demonstrated by using cross-gain modulation (XGM) technology of semiconductor optical amplifiers (SOAs) all-optical XOR logic gates. Operation speed of 10 Gbps encryption and decryption operations are successfully obtained.

All-optical signal processing using semiconductor optical amplifier based logic gates

Some of all-optical signal processing techniques using all-optical logic gates based on semiconductor optical amplifiers have been demonstrated at 10 Gbps. The primary techniques for all-optical signal processing such as label swapping and data extraction are successfully demonstrated using VPI simulation tool lntroductlon As the speed of telecommunication systems increases and reaches the limit of electronic devices, the demands for all-optical signal processing techniques such as label or packet switching, decision making, regenerating, and basic or complex computing are rapidly increasing. Current communication systems usually require various ailoptical logic gates such as AND, OR, XOR, NAND, NOR, and XNOR. However, their applications are very limited to small numbers [ l , 21. Also, logic implementation techniques are usually limited to mach-zehnder interferometer and fiber-based devices while our logic gates are mostly based on semiconductor optical amplifiers (SOA?. ) In this paper, the primary techniques of all-optical label swapping and data extraction using semiconductor optical amplifiers are demonstrated at 10 Gbps using VPI simulation tool. Operation principles In this paper, to implement the all-optical label swapping and data extraction among various alloptical signal processing techniques, only one mechanism that is cross-gain modulation (XGM) of SOAs is used. To realize the all-optical label swapping, an all-optical XOR gate using two SOAs is utilized. Operation principle of the XOR gate is shown in Fig. 1 [3].

Simulation and Realization of Simultaneous Operation of All-Optical NOR, AND, XNOR Gates Using Semiconductor Optical Amplifiers

We simulated and demonstrated all-optical multi-functional logic gates for simultaneous operations at 10 Gbps. All-optical XNOR, NOR and AND operations are simultaneously realized in this work.