Design of an Ultra-Compact and High-Contrast Ratio All-Optical NOR Gate

Abstract

In this research, an all-optical NOR gate is designed and simulated based on two-dimensional photonic crystals. A square lattice has been used to design this structure. This logic gate has two main inputs, a bias input and an output. Because the output of the NOR gate must be “1” for zero inputs, a bias input is required. One of the characteristics of this structure is its small size for use in optical integrated circuits. Also, in order to reduce the detection error in the output, it has been tried that the outputs have a suitable distance in two “0” and “1” logical states. The use of a small number and simple point defects makes the design of this gate easier. The simulation results show that the proposed structure is suitable for working at a wavelength of 1.55µm. Also, the amount of optical power at the output is high in the “1” logical mode and low in the “0” logical mode. This indicates that this structure has a reliable output for detecting logical values. In this paper, a photonic crystal structure is proposed to realize the NOR logic gate, which is small in size and uses simple linear and point defects. The use of very few point defects has made the design simpler and thus easier to build this gate. Due to these characteristics, this structure can be suitable for optically integrated circuits.

Optimal Solar Greenhouses Design Using Multiobjective Genetic Algorithm

“…As it mentioned before, latitude of Rasht city is  37 28 . More details regarding the relations among the solar angles can be found in [39][40][41].…”

“…In a recent research, Mahjoob Karambasti et al [24] determined the optimal orientation and roof inclination angle of an even-span greenhouse with fixed floor area by employing a multiobjective optimization (MOGA) method and solar radiation distribution model for northern sections of Iran. It should be mentioned that apart from GA and PSO approaches, other nature-based and numerical algorithms, [25][26][27][28][29][30], [31][32][33], [34][35][36][37], such as gray wolf optimization, ant colony, neural networks and other types of natured based and numerical algorithms can be adopted for greenhouse optimal condition improvement.…”

Efficient and Compact Optical NOR Gate based on Photonic Crystal Platform

“…The suggested all optical NOR gate has an improvement of 40% which makes it a practical design for photonic integrated circuits (PICs). Further, a rapid temporal response of 1.2 PS is achieved with a switching rate of 133GHz which is slower than those introduced in [10,11,19,20,21,22]. Finally, the suggested NOR gate can be used to boast the optical computing and signal processing.…”

“…In reference [21], a NOR gate with an out power of 68 % of the input power when the state is ON and 7 %, while the state is off, is described. The NOR gate was presented in reference [22] with an out power of 60% at ON and 5% at off states with a switching rate of 3.4 ps.…”

“…Further, NOR gate has been proposed with an out power of 90% from the input power at ON state and less than 5% when the state is off [19]. In reference [21] a NOR gate with an out power of 68% of the input power while the state is ON and 7% when the state is off. The NOR gate has been proposed in reference [22] with an out power of 60% at ON state and 5% at off states with a switching rate of 3.4 ps.…”