We propose AND, NOR, and XNOR logic gates realized simultaneously for 40-Gb/s networks, in which the realization of NOR and XNOR logic gates using only MgO-doped periodically poled lithium niobate (MgO: PPLN) is reported. In our configuration, we exploit broadband quasi-phase matching (QPM) cascaded second harmonic and difference-frequency generation (cSHG/DFG), cascaded sum-frequency and difference-frequency generation (cSFG/DFG) in one MgO:PPLN, and the narrow band QPM sum-frequency generation (SFG) in another MgO:PPLN. The performance, including the quality-factor (Q-factor) and extinction ratio (ER), of the proposed multifunctional logic device is also simulated.

We propose and describe an all-optical prefix tree adder with the help of a terahertz optical asymmetric demultiplexer (TOAD) using a set of optical switches. The prefix tree adder is useful in compound adder implementation. It is preferred over the ripple carry adder and the carry lookahead adder. We also describe the principle and possibilities of the all-optical prefix tree adder. The theoretical model is presented and verified through numerical simulation. The new method promises higher processing speed and accuracy. The model can be extended for studying more complex all-optical circuits of enhanced functionality in which the prefix tree adder is the basic building block.

We introduce a novel network-coding scheme that can be implemented in all-optical multicast networks. A simple and successful module based on the all-optical XOR gate is designed to realize the network coding scheme. The module is a key hardware component in realizing the proposed scheme. The working principle and the experimental results of the module are also presented. Experimental results show that the function of the module is sufficient in satisfying the requirements of the proposed network coding scheme.

Over the last few decades, several all-optical circuits have been proposed to meet the need of high-speed data processing. In some information processing architectures, the role of various analog and digital data comparisons is very important. In this letter, we proposed a multi-bit data comparison scheme. The scheme is based on the switching property of optical nonlinear material. Ultrafast operational speed larger than gigahertz can be expected from this all-optical scheme.

The advantages of multivalued logic in optical parallel computation need no introduction. There are lots of proposals, already reported, where tristate, quarternary state logic operations can be performed with optics. Here we report a new approach to implement tristate logic based all optical flip-flop using optical nonlinear material. The concept and the principle of operation of this type of flip-flop are different from that of the conventional binary one.

The limitations in electronics in arithmetic, algebraic & logic processing are well known. Very high speed performance (above GHz) are not expected at all in conventional electronic mechanism. To achieve high speed performance we may think on the introduction of optics instead of electronics for information processing and computing. Non-linear optical material is a successful candidate in this regard to play a major role in the optically controlled switching systems and therefore in all-optical parallel computation these materials can show a very good potential aspect. In this paper, we have proposed a new method of an optical half adder as well as full adder circuit for binary addition using non-linear and linear optical materials.