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In this paper, a new structure of 2D photonic crystals for all-optical 4-bit adder based on kerr effect and ring resonators is proposed. The fundamental rods are made of silicon material with a refractive index is about 3.476 around a wavelength 1550 nm. The lattice constant of the PhC structure, and the radii of fundamental dielectric rods are about 592 nm, and 118 nm, respectively. The structure is designed using in a cascade one half adder and three full adders. The optical adder is composed of nonlinear ring resonators, input ports (Ai, Bi), and output ports (Si, Ci). The ring resonators R1 and R2 based on the optical kerr effect are created by replacing 2 × 24 dielectric rods are made of nonlinear material doped glass with a linear and nonlinear refractive index of 1.4 and 10−14 m2/W, respectively. The radii of these dielectric rods are 90 nm and 80 nm. The input and output ports are located in the best position, and the total footprint is about 2229 μm2. We used COMSOL Multiphysics Software based on the plane wave expansion and the finite element methods to simulate the photonic band gap diagram and the light propagation inside the PhC structure. The proposed 4-bit adder can be used in the next generation of optical computer systems applications and photonic integrated circuit communication. [ABSTRACT FROM AUTHOR]

In this paper, we propose a new design of an all-optical 2-bit adder based on Photonic Crystal nonlinear ring resonators. The proposed structure is designed by cascading one optical half adder and one full adder composed of nonlinear ring resonators. The Photonic Crystal (PhC) based 2-bit adder consists of four input ports (A0, B0, A1, and B1), and three output ports for SUM and CARRY (S0, S1, and C1). The contrast ratios of the output ports S0, S1, C1 are about 16.62 dB and 16.33 dB, and 15.13 dB, respectively. The optical 2-bit adder is simulated at the C-band communication window (at the wavelength 1550 nm). The plane wave expansion (PWEM) and the finite element methods are used to study the photonic band structure and the light propagation inside the optical 2-bit adder. [ABSTRACT FROM AUTHOR]

In this paper, we have presented a new design of an all-optical full-adder using dual nonlinear ring resonators. The PhC based full adder consists of three input ports (A, B, and Cin), two half adders based nonlinear ring resonators, a logic gate stage, and two output ports for ''SUM" and ''CARRY". The footprint and contrast ratios of the proposed full adder are about 635 μm2, 19.34 dB, and 15.96 dB, respectively. The advantages of non-linearity are the normalized power difference with high and low logical values improves the constant ratios. The plane wave expansion (PWE) and the finite element methods are used to study the photonic band structure and the light propagation inside the full adder under COMSOL Multiphysics Software. [ABSTRACT FROM AUTHOR]

In this paper, we have presented an efficient original architecture of all-optical 2 × 4 photonic crystal decoder based on non-linear ring resonators. The fundamental structure is a square lattice of 2D GaAs rods, operating around the wavelength 1.55 µm. The proposed decoder is composed of a combiner with three input ports, where the port E is used for excitation and A1, A2 are the control ports, and an optical switch with four output ports, and it is a nonlinear DMEX. For the creation of a switch at the wavelength of 1.55 µm, we used nonlinear chalcogenide glass rods with a nonlinear Kerr coefficient equal to 9 × 10–17 m2/w. The switching intensity and structure size are 1 Kw/µm2, 27.12 µm × 17.96 µm, respectively. The contrast ratio is about 8.7. The maximum crosstalk and insertion losses are calculated to be about − 22.1 and − 4.5 dB. The maximum and minimum power levels for logic states 0 and 1 are 0.05 × P0 and 0.37 × P0 where P0 is the input power. The finite element method was used to perform the necessary calculations. [ABSTRACT FROM AUTHOR]